merge viewer-release to sunshine-external

53 files changed, 5871 insertions, 1523 deletions

diff --git a/.hgtags b/.hgtags
index ab6fe3635b..30e96d4a18 100755
--- a/.hgtags
+++ b/.hgtags
@@ -474,3 +474,4 @@ d40c66e410741de7e90b1ed6dac28dd8a2d7e1f6 3.6.8-release
 0d9b9e50f1a8880e05f15688a9ec7d09e0e81013 3.6.13-release
 5d746de933a98ca17887cde2fece80e9c7ab0b98 3.7.0-release
 dcb4981ce255841b6083d8f65444b65d5a733a17 3.7.1-release
+b842534cb4d76c9ef87676a62b1d2d19e79c015f 3.7.2-release
diff --git a/autobuild.xml b/autobuild.xml
index c213dc0d99..3d8f7c22b1 100755
--- a/autobuild.xml
+++ b/autobuild.xml
@@ -282,9 +282,9 @@
             <key>archive</key>
             <map>
               <key>hash</key>
-              <string>aaea644191807f51051cefa2fac11069</string>
+              <string>f7d9b6a9c624364389b71209881f39de</string>
               <key>url</key>
-              <string>http://s3.amazonaws.com/viewer-source-downloads/install_pkgs/curl-7.21.1-darwin-20110316.tar.bz2</string>
+              <string>http://automated-builds-secondlife-com.s3.amazonaws.com/hg/repo/3p-curl/rev/280289/arch/Darwin/installer/curl-7.24.0-darwin-20130826.tar.bz2</string>
             </map>
             <key>name</key>
             <string>darwin</string>
@@ -294,9 +294,9 @@
             <key>archive</key>
             <map>
               <key>hash</key>
-              <string>2d9377951d99a1aa4735cea8d4b5aa71</string>
+              <string>58b7bf45383c1b1bc24afb303b1519c8</string>
               <key>url</key>
-              <string>http://s3.amazonaws.com/viewer-source-downloads/install_pkgs/curl-7.21.1-linux-20110316.tar.bz2</string>
+              <string>http://automated-builds-secondlife-com.s3.amazonaws.com/hg/repo/3p-curl/rev/280289/arch/Linux/installer/curl-7.24.0-linux-20130826.tar.bz2</string>
             </map>
             <key>name</key>
             <string>linux</string>
@@ -306,9 +306,9 @@
             <key>archive</key>
             <map>
               <key>hash</key>
-              <string>fea96aa2a7d513397317194f3d6c979b</string>
+              <string>8d9ccb0277a26bfe3f346c3c49ce4b58</string>
               <key>url</key>
-              <string>http://s3.amazonaws.com/viewer-source-downloads/install_pkgs/curl-7.21.1-windows-20110211.tar.bz2</string>
+              <string>http://automated-builds-secondlife-com.s3.amazonaws.com/hg/repo/3p-curl/rev/280289/arch/CYGWIN/installer/curl-7.24.0-windows-20130826.tar.bz2</string>
             </map>
             <key>name</key>
             <string>windows</string>
diff --git a/indra/edit-me-to-trigger-new-build.txt b/indra/edit-me-to-trigger-new-build.txt
index 48e8b566a6..c63ad74682 100755
--- a/indra/edit-me-to-trigger-new-build.txt
+++ b/indra/edit-me-to-trigger-new-build.txt
@@ -1 +1 @@
-Mon Apr 15 14:35:39 EDT 2013
+2014-02-25 10:34
diff --git a/indra/llcommon/CMakeLists.txt b/indra/llcommon/CMakeLists.txt
index 66995d8083..b0ed763aa1 100755
--- a/indra/llcommon/CMakeLists.txt
+++ b/indra/llcommon/CMakeLists.txt
@@ -43,6 +43,7 @@ set(llcommon_SOURCE_FILES
     llcriticaldamp.cpp
     llcursortypes.cpp
     lldate.cpp
+    lldeadmantimer.cpp
     lldependencies.cpp
     lldictionary.cpp
     llerror.cpp
@@ -79,6 +80,7 @@ set(llcommon_SOURCE_FILES
     llptrto.cpp 
     llprocess.cpp
     llprocessor.cpp
+    llprocinfo.cpp
     llqueuedthread.cpp
     llrand.cpp
     llrefcount.cpp
@@ -146,6 +148,7 @@ set(llcommon_HEADER_FILES
     lldarray.h
     lldarrayptr.h
     lldate.h
+    lldeadmantimer.h
     lldefs.h
     lldependencies.h
     lldeleteutils.h
@@ -206,6 +209,7 @@ set(llcommon_HEADER_FILES
     llpriqueuemap.h
     llprocess.h
     llprocessor.h
+    llprocinfo.h
     llptrskiplist.h
     llptrskipmap.h
     llptrto.h
@@ -323,12 +327,14 @@ if (LL_TESTS)
   LL_ADD_INTEGRATION_TEST(bitpack "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llbase64 "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(lldate "" "${test_libs}")
+  LL_ADD_INTEGRATION_TEST(lldeadmantimer "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(lldependencies "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llerror "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llframetimer "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llinstancetracker "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(lllazy "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llprocessor "" "${test_libs}")
+  LL_ADD_INTEGRATION_TEST(llprocinfo "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llrand "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llsdserialize "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llsingleton "" "${test_libs}")                          
diff --git a/indra/llcommon/lldeadmantimer.cpp b/indra/llcommon/lldeadmantimer.cpp
new file mode 100644
index 0000000000..7d9097e344
--- /dev/null
+++ b/indra/llcommon/lldeadmantimer.cpp
@@ -0,0 +1,188 @@
+/** 
+* @file lldeadmantimer.cpp
+* @brief Simple deadman-switch timer.
+* @author monty@lindenlab.com
+*
+* $LicenseInfo:firstyear=2013&license=viewerlgpl$
+* Second Life Viewer Source Code
+* Copyright (C) 2013, Linden Research, Inc.
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation;
+* version 2.1 of the License only.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*
+* Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+* $/LicenseInfo$
+*/
+
+
+#include "lldeadmantimer.h"
+
+
+// *TODO:  Currently, this uses lltimer functions for its time
+// aspects and this leaks into the apis in the U64s/F64s.  Would
+// like to perhaps switch this over to TSC register-based timers
+// sometime and drop the overhead some more.
+
+
+//  Flag states and their meaning:
+//  mActive  mDone   Meaning
+//   false   false   Nothing running, no result available
+//    true   false   Timer running, no result available
+//   false    true   Timer finished, result can be read once
+//    true    true   Not allowed
+//
+LLDeadmanTimer::LLDeadmanTimer(F64 horizon, bool inc_cpu)
+	: mHorizon(time_type(llmax(horizon, F64(0.0)) * gClockFrequency)),
+	  mActive(false),			// If true, a timer is running.
+	  mDone(false),				// If true, timer has completed and can be read (once)
+	  mStarted(U64L(0)),
+	  mExpires(U64L(0)),
+	  mStopped(U64L(0)),
+	  mCount(U64L(0)),
+	  mIncCPU(inc_cpu),
+	  mUStartCPU(LLProcInfo::time_type(U64L(0))),
+	  mUEndCPU(LLProcInfo::time_type(U64L(0))),
+	  mSStartCPU(LLProcInfo::time_type(U64L(0))),
+	  mSEndCPU(LLProcInfo::time_type(U64L(0)))
+{}
+
+
+// static
+LLDeadmanTimer::time_type LLDeadmanTimer::getNow()
+{
+	return LLTimer::getCurrentClockCount();
+}
+
+
+void LLDeadmanTimer::start(time_type now)
+{
+	// *TODO:  If active, let's complete an existing timer and save
+	// the result to the side.  I think this will be useful later.
+	// For now, wipe out anything in progress, start fresh.
+	
+	if (! now)
+	{
+		now = LLTimer::getCurrentClockCount();
+	}
+	mActive = true;
+	mDone = false;
+	mStarted = now;
+	mExpires = now + mHorizon;
+	mStopped = now;
+	mCount = U64L(0);
+	if (mIncCPU)
+	{
+		LLProcInfo::getCPUUsage(mUStartCPU, mSStartCPU);
+	}
+}
+
+
+void LLDeadmanTimer::stop(time_type now)
+{
+	if (! mActive)
+	{
+		return;
+	}
+
+	if (! now)
+	{
+		now = getNow();
+	}
+	mStopped = now;
+	mActive = false;
+	mDone = true;
+	if (mIncCPU)
+	{
+		LLProcInfo::getCPUUsage(mUEndCPU, mSEndCPU);
+	}
+}
+
+
+bool LLDeadmanTimer::isExpired(time_type now, F64 & started, F64 & stopped, U64 & count,
+							   U64 & user_cpu, U64 & sys_cpu)
+{
+	const bool status(isExpired(now, started, stopped, count));
+	if (status)
+	{
+		user_cpu = U64(mUEndCPU - mUStartCPU);
+		sys_cpu = U64(mSEndCPU - mSStartCPU);
+	}
+	return status;
+}
+
+		
+bool LLDeadmanTimer::isExpired(time_type now, F64 & started, F64 & stopped, U64 & count)
+{
+	if (mActive && ! mDone)
+	{
+		if (! now)
+		{
+			now = getNow();
+		}
+
+		if (now >= mExpires)
+		{
+			// mStopped from ringBell() is the value we want
+			mActive = false;
+			mDone = true;
+		}
+	}
+
+	if (! mDone)
+	{
+		return false;
+	}
+	
+	started = mStarted * gClockFrequencyInv;
+	stopped = mStopped * gClockFrequencyInv;
+	count = mCount;
+	mDone = false;
+
+	return true;
+}
+
+	
+void LLDeadmanTimer::ringBell(time_type now, unsigned int count)
+{
+	if (! mActive)
+	{
+		return;
+	}
+	
+	if (! now)
+	{
+		now = getNow();
+	}
+
+	if (now >= mExpires)
+	{
+		// Timer has expired, this event will be dropped
+		mActive = false;
+		mDone = true;
+	}
+	else
+	{
+		// Timer renewed, keep going
+		mStopped = now;
+		mExpires = now + mHorizon;
+		mCount += count;
+		if (mIncCPU)
+		{
+			LLProcInfo::getCPUUsage(mUEndCPU, mSEndCPU);
+		}
+	}
+	
+	return;
+}
+
diff --git a/indra/llcommon/lldeadmantimer.h b/indra/llcommon/lldeadmantimer.h
new file mode 100644
index 0000000000..980976e176
--- /dev/null
+++ b/indra/llcommon/lldeadmantimer.h
@@ -0,0 +1,214 @@
+/** 
+* @file   lldeadmantimer.h
+* @brief  Interface to a simple event timer with a deadman's switch
+* @author monty@lindenlab.com
+*
+* $LicenseInfo:firstyear=2013&license=viewerlgpl$
+* Second Life Viewer Source Code
+* Copyright (C) 2013, Linden Research, Inc.
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation;
+* version 2.1 of the License only.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*
+* Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+* $/LicenseInfo$
+*/
+
+#ifndef	LL_DEADMANTIMER_H
+#define	LL_DEADMANTIMER_H
+
+
+#include "linden_common.h"
+
+#include "lltimer.h"
+#include "llprocinfo.h"
+
+
+/// @file lldeadmantimer.h
+///
+/// There are interesting user-experienced events in the viewer that
+/// would seem to have well-defined start and stop points but which
+/// actually lack such milestones in the code.  Such events (like
+/// time to load meshes after logging in, initial inventory load,
+/// display name fetch) can be defined somewhat after-the-fact by
+/// noticing when we no longer perform operations towards their
+/// completion.  This class is intended to help in such applications.
+///
+/// What it implements is a deadman's switch (also known as a
+/// keepalive switch and a doorbell switch).  The basic operation is
+/// as follows:
+///
+/// * LLDeadmanTimer is instantiated with a horizon value in seconds,
+///   one for each event of interest.
+/// * When an event starts, @see start() is invoked to begin a
+///   timing operation.
+/// * As operations are performed in service of the event (issuing
+///   HTTP requests, receiving responses), @see ringBell() is invoked
+///   to inform the timer that the operation is still active.
+/// * If the operation is canceled or otherwise terminated, @see
+///   stop() can be called to end the timing operation.
+/// * Concurrent with the ringBell() calls, the program makes
+///   periodic (shorter than the horizon but not too short) calls
+///   to @see isExpired() to see if the event has expired due to
+///   either a stop() call or lack of activity (defined as a ringBell()
+///   call in the previous 'horizon' seconds).  If it has expired,
+///   the caller also receives start, stop and count values for the
+///   event which the application can then report in whatever manner
+///   it sees fit.
+/// * The timer becomes passive after an isExpired() call that returns
+///   true.  It can then be restarted with a new start() call.
+///
+/// Threading:  Instances are not thread-safe.  They also use
+/// timing code from lltimer.h which is also unsafe.
+///
+/// Allocation:  Not refcounted, may be stack or heap allocated.
+///
+
+class LL_COMMON_API LLDeadmanTimer
+{
+public:
+	/// Public types
+
+	/// Low-level time type chosen for compatibility with
+	/// LLTimer::getCurrentClockCount() which is the basis
+	/// of time operations in this class.  This is likely
+	/// to change in a future version in a move to TSC-based
+	/// timing.
+	typedef U64 time_type;
+	
+public:
+	/// Construct and initialize an LLDeadmanTimer
+	///
+	/// @param horizon	Time, in seconds, after the last @see ringBell()
+	///                 call at which point the timer will consider itself
+	///					expired.
+	///
+	/// @param inc_cpu	If true, gather system and user cpu stats while
+	///					running the timer.  This does require more syscalls
+	///					during updates.  If false, cpu usage data isn't
+	///					collected and will be zero if queried.
+	LLDeadmanTimer(F64 horizon, bool inc_cpu);
+
+	~LLDeadmanTimer() 
+		{}
+	
+private:
+	LLDeadmanTimer(const LLDeadmanTimer &);				// Not defined
+	void operator=(const LLDeadmanTimer &);				// Not defined
+
+public:
+	/// Get the current time.  Zero-basis for this time
+	/// representation is not defined and is different on
+	/// different platforms.  Do not attempt to compute
+	/// negative times relative to the first value returned,
+	/// there may not be enough 'front porch' on the range
+	/// to prevent wraparound.
+	///
+	/// Note:  Implementation is expected to change in a
+	/// future release as well.
+	///
+	static time_type getNow();
+
+	/// Begin timing.  If the timer is already active, it is reset
+	///	and timing begins now.
+	///
+	/// @param now		Current time as returned by @see
+	///					LLTimer::getCurrentClockCount().  If zero,
+	///					method will lookup current time.
+	///
+	void start(time_type now);
+
+	/// End timing.  Actively declare the end of the event independent
+	/// of the deadman's switch operation.  @see isExpired() will return
+	/// true and appropriate values will be returned.
+	///
+	/// @param now		Current time as returned by @see
+	///					LLTimer::getCurrentClockCount().  If zero,
+	///					method will lookup current time.
+	///
+	void stop(time_type now);
+
+	/// Declare that something interesting happened.  This has two
+	/// effects on an unexpired-timer.  1)  The expiration time
+	/// is extended for 'horizon' seconds after the 'now' value.
+	/// 2)  An internal counter associated with the event is incremented
+	/// by the @ref count parameter.  This count is returned via the
+	/// @see isExpired() method.
+	///
+	/// @param now		Current time as returned by @see
+	///					LLTimer::getCurrentClockCount().  If zero,
+	///					method will lookup current time.
+	///
+	/// @param count	Count of events to be associated with
+	///					this bell ringing.
+	///
+	void ringBell(time_type now, unsigned int count);
+	
+	/// Checks the status of the timer.  If the timer has expired,
+	/// also returns various timer-related stats.  Unlike ringBell(),
+	/// does not extend the horizon, it only checks for expiration.
+	///
+	/// @param now		Current time as returned by @see
+	///					LLTimer::getCurrentClockCount().  If zero,
+	///					method will lookup current time.
+	///
+	/// @param started	If expired, the starting time of the event is
+	///					returned to the caller via this reference.
+	///
+	/// @param stopped	If expired, the ending time of the event is
+	///					returned to the caller via this reference.
+	///					Ending time will be that provided in the
+	///					stop() method or the last ringBell() call
+	///					leading to expiration, whichever (stop() call
+	///					or notice of expiration) happened first.
+	///
+	/// @param count	If expired, the number of ringBell() calls
+	///					made prior to expiration.
+	///
+	/// @param user_cpu	Amount of CPU spent in user mode by the process
+	///					during the event.  Value in microseconds and will
+	///					read zero if not enabled by the constructor.
+	///
+	/// @param sys_cpu	Amount of CPU spent in system mode by the process.
+	///
+	/// @return			true if the timer has expired, false otherwise.
+	///					If true, it also returns the started,
+	///					stopped and count values otherwise these are
+	///					left unchanged.
+	///
+	bool isExpired(time_type now, F64 & started, F64 & stopped, U64 & count,
+				   U64 & user_cpu, U64 & sys_cpu);
+
+	/// Identical to the six-arugment form except it does without the
+	/// CPU time return if the caller isn't interested in it.
+	bool isExpired(time_type now, F64 & started, F64 & stopped, U64 & count);
+
+protected:
+	time_type					mHorizon;
+	bool						mActive;
+	bool						mDone;
+	time_type					mStarted;
+	time_type					mExpires;
+	time_type					mStopped;
+	time_type					mCount;
+
+	const bool					mIncCPU;		// Include CPU metrics in timer
+	LLProcInfo::time_type		mUStartCPU;
+	LLProcInfo::time_type		mUEndCPU;
+	LLProcInfo::time_type		mSStartCPU;
+	LLProcInfo::time_type		mSEndCPU;
+};
+	
+
+#endif	// LL_DEADMANTIMER_H
diff --git a/indra/llcommon/llprocinfo.cpp b/indra/llcommon/llprocinfo.cpp
new file mode 100644
index 0000000000..c00f979b0b
--- /dev/null
+++ b/indra/llcommon/llprocinfo.cpp
@@ -0,0 +1,94 @@
+/** 
+* @file llprocinfo.cpp
+* @brief Process, cpu and resource usage information APIs.
+* @author monty@lindenlab.com
+*
+* $LicenseInfo:firstyear=2013&license=viewerlgpl$
+* Second Life Viewer Source Code
+* Copyright (C) 2013, Linden Research, Inc.
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation;
+* version 2.1 of the License only.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*
+* Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+* $/LicenseInfo$
+*/
+
+
+#include "llprocinfo.h"
+
+#if LL_WINDOWS
+
+#define	PSAPI_VERSION	1
+#include "windows.h"
+#include "psapi.h"
+
+#elif LL_DARWIN
+
+#include <sys/resource.h>
+#include <mach/mach.h>
+	
+#else
+
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#endif // LL_WINDOWS/LL_DARWIN
+
+
+// static
+void LLProcInfo::getCPUUsage(time_type & user_time, time_type & system_time)
+{
+#if LL_WINDOWS
+
+	HANDLE self(GetCurrentProcess());			// Does not have to be closed
+	FILETIME ft_dummy, ft_system, ft_user;
+
+	GetProcessTimes(self, &ft_dummy, &ft_dummy, &ft_system, &ft_user);
+	ULARGE_INTEGER uli;
+	uli.u.LowPart = ft_system.dwLowDateTime;
+	uli.u.HighPart = ft_system.dwHighDateTime;
+	system_time = uli.QuadPart / U64L(10);		// Convert to uS
+	uli.u.LowPart = ft_user.dwLowDateTime;
+	uli.u.HighPart = ft_user.dwHighDateTime;
+	user_time = uli.QuadPart / U64L(10);
+	
+#elif LL_DARWIN
+
+	struct rusage usage;
+
+	if (getrusage(RUSAGE_SELF, &usage))
+	{
+		user_time = system_time = time_type(0U);
+		return;
+	}
+	user_time = U64(usage.ru_utime.tv_sec) * U64L(1000000) + usage.ru_utime.tv_usec;
+	system_time = U64(usage.ru_stime.tv_sec) * U64L(1000000) + usage.ru_stime.tv_usec;
+
+#else // Linux
+
+	struct rusage usage;
+
+	if (getrusage(RUSAGE_SELF, &usage))
+	{
+		user_time = system_time = time_type(0U);
+		return;
+	}
+	user_time = U64(usage.ru_utime.tv_sec) * U64L(1000000) + usage.ru_utime.tv_usec;
+	system_time = U64(usage.ru_stime.tv_sec) * U64L(1000000) + usage.ru_stime.tv_usec;
+	
+#endif // LL_WINDOWS/LL_DARWIN/Linux
+}
+
+
diff --git a/indra/llcommon/llprocinfo.h b/indra/llcommon/llprocinfo.h
new file mode 100644
index 0000000000..e78bcf490a
--- /dev/null
+++ b/indra/llcommon/llprocinfo.h
@@ -0,0 +1,68 @@
+/** 
+* @file   llprocinfo.h
+* @brief  Interface to process/cpu/resource information services.
+* @author monty@lindenlab.com
+*
+* $LicenseInfo:firstyear=2013&license=viewerlgpl$
+* Second Life Viewer Source Code
+* Copyright (C) 2013, Linden Research, Inc.
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation;
+* version 2.1 of the License only.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*
+* Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+* $/LicenseInfo$
+*/
+
+#ifndef	LL_PROCINFO_H
+#define	LL_PROCINFO_H
+
+
+#include "linden_common.h"
+
+/// @file llprocinfo.h
+///
+/// Right now, this is really a namespace disguised as a class.
+/// It wraps some types and functions to return information about
+/// process resource consumption in a non-OS-specific manner.
+///
+/// Threading:  No instances so that's thread-safe.  Implementations
+/// of static functions should be thread-safe, they mostly involve
+/// direct syscall invocations.
+///
+/// Allocation:  Not instantiatable.
+
+class LL_COMMON_API LLProcInfo
+{
+public:
+	/// Public types
+
+	typedef U64 time_type;								/// Relative microseconds
+	
+private:
+	LLProcInfo();										// Not defined
+	~LLProcInfo();										// Not defined
+	LLProcInfo(const LLProcInfo &);						// Not defined
+	void operator=(const LLProcInfo &);					// Not defined
+
+public:
+	/// Get accumulated system and user CPU time in
+	/// microseconds.  Syscalls involved in every invocation.
+	///
+	/// Threading:  expected to be safe.
+	static void getCPUUsage(time_type & user_time, time_type & system_time);
+};
+	
+
+#endif	// LL_PROCINFO_H
diff --git a/indra/llcommon/llthread.cpp b/indra/llcommon/llthread.cpp
index 60adeeaeb7..e67d1bc57b 100755
--- a/indra/llcommon/llthread.cpp
+++ b/indra/llcommon/llthread.cpp
@@ -3,7 +3,7 @@
  *
  * $LicenseInfo:firstyear=2004&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2010, Linden Research, Inc.
+ * Copyright (C) 2010-2013, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -373,6 +373,36 @@ void LLMutex::lock()
 #endif
 }
 
+bool LLMutex::trylock()
+{
+	if(isSelfLocked())
+	{ //redundant lock
+		mCount++;
+		return true;
+	}
+	
+	apr_status_t status(apr_thread_mutex_trylock(mAPRMutexp));
+	if (APR_STATUS_IS_EBUSY(status))
+	{
+		return false;
+	}
+	
+#if MUTEX_DEBUG
+	// Have to have the lock before we can access the debug info
+	U32 id = LLThread::currentID();
+	if (mIsLocked[id] != FALSE)
+		llerrs << "Already locked in Thread: " << id << llendl;
+	mIsLocked[id] = TRUE;
+#endif
+
+#if LL_DARWIN
+	mLockingThread = LLThread::currentID();
+#else
+	mLockingThread = sThreadID;
+#endif
+	return true;
+}
+
 void LLMutex::unlock()
 {
 	if (mCount > 0)
diff --git a/indra/llcommon/llthread.h b/indra/llcommon/llthread.h
index f51d985b5f..8c7143304f 100755
--- a/indra/llcommon/llthread.h
+++ b/indra/llcommon/llthread.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2004&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2010, Linden Research, Inc.
+ * Copyright (C) 2010-2013, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -156,7 +156,8 @@ public:
 	virtual ~LLMutex();
 	
 	void lock();		// blocks
-	void unlock();
+	bool trylock();		// non-blocking, returns true if lock held.
+	void unlock();		// undefined behavior when called on mutex not being held
 	bool isLocked(); 	// non-blocking, but does do a lock/unlock so not free
 	bool isSelfLocked(); //return true if locked in a same thread
 	U32 lockingThread() const; //get ID of locking thread
@@ -174,6 +175,8 @@ protected:
 #endif
 };
 
+//============================================================================
+
 // Actually a condition/mutex pair (since each condition needs to be associated with a mutex).
 class LL_COMMON_API LLCondition : public LLMutex
 {
@@ -189,6 +192,8 @@ protected:
 	apr_thread_cond_t *mAPRCondp;
 };
 
+//============================================================================
+
 class LLMutexLock
 {
 public:
@@ -210,6 +215,43 @@ private:
 
 //============================================================================
 
+// Scoped locking class similar in function to LLMutexLock but uses
+// the trylock() method to conditionally acquire lock without
+// blocking.  Caller resolves the resulting condition by calling
+// the isLocked() method and either punts or continues as indicated.
+//
+// Mostly of interest to callers needing to avoid stalls who can
+// guarantee another attempt at a later time.
+
+class LLMutexTrylock
+{
+public:
+	LLMutexTrylock(LLMutex* mutex)
+		: mMutex(mutex),
+		  mLocked(false)
+	{
+		if (mMutex)
+			mLocked = mMutex->trylock();
+	}
+
+	~LLMutexTrylock()
+	{
+		if (mMutex && mLocked)
+			mMutex->unlock();
+	}
+
+	bool isLocked() const
+	{
+		return mLocked;
+	}
+	
+private:
+	LLMutex*	mMutex;
+	bool		mLocked;
+};
+
+//============================================================================
+
 void LLThread::lockData()
 {
 	mDataLock->lock();
diff --git a/indra/llcommon/lltimer.h b/indra/llcommon/lltimer.h
index 513de0605d..e73741217c 100755
--- a/indra/llcommon/lltimer.h
+++ b/indra/llcommon/lltimer.h
@@ -146,6 +146,13 @@ static inline time_t time_max()
 	}
 }
 
+// These are really statics but they've been global for awhile
+// and they're material to other timing classes.  If you are
+// not implementing a timer class, do not use these directly.
+extern LL_COMMON_API F64 gClockFrequency;
+extern LL_COMMON_API F64 gClockFrequencyInv;
+extern LL_COMMON_API F64 gClocksToMicroseconds;
+
 // Correction factor used by time_corrected() above.
 extern LL_COMMON_API S32 gUTCOffset;
 
diff --git a/indra/llcommon/tests/lldeadmantimer_test.cpp b/indra/llcommon/tests/lldeadmantimer_test.cpp
new file mode 100644
index 0000000000..7fd2dde6e0
--- /dev/null
+++ b/indra/llcommon/tests/lldeadmantimer_test.cpp
@@ -0,0 +1,628 @@
+/** 
+ * @file lldeadmantimer_test.cpp
+ * @brief Tests for the LLDeadmanTimer class.
+ *
+ * $LicenseInfo:firstyear=2013&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2013, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include "linden_common.h"
+
+#include "../lldeadmantimer.h"
+#include "../llsd.h"
+#include "../lltimer.h"
+
+#include "../test/lltut.h"
+
+// Convert between floating point time deltas and U64 time deltas.
+// Reflects an implementation detail inside lldeadmantimer.cpp
+
+static LLDeadmanTimer::time_type float_time_to_u64(F64 delta)
+{
+	return LLDeadmanTimer::time_type(delta * gClockFrequency);
+}
+
+static F64 u64_time_to_float(LLDeadmanTimer::time_type delta)
+{
+	return delta * gClockFrequencyInv;
+}
+
+
+namespace tut
+{
+
+struct deadmantimer_test
+{
+	deadmantimer_test()
+		{
+			// LLTimer internals updating
+			update_clock_frequencies();
+		}
+};
+
+typedef test_group<deadmantimer_test> deadmantimer_group_t;
+typedef deadmantimer_group_t::object deadmantimer_object_t;
+tut::deadmantimer_group_t deadmantimer_instance("LLDeadmanTimer");
+
+// Basic construction test and isExpired() call
+template<> template<>
+void deadmantimer_object_t::test<1>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(10.0, false);
+
+		ensure_equals("WOCM isExpired() returns false after ctor()", timer.isExpired(0, started, stopped, count), false);
+		ensure_approximately_equals("WOCM t1 - isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WOCM t1 - isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WOCM t1 - isExpired() does not modify count", count, U64L(8));
+	}
+
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(10.0, true);
+
+		ensure_equals("WCM isExpired() returns false after ctor()", timer.isExpired(0, started, stopped, count, user_cpu, sys_cpu), false);
+		ensure_approximately_equals("WCM t1 - isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WCM t1 - isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WCM t1 - isExpired() does not modify count", count, U64L(8));
+		ensure_equals("WCM t1 - isExpired() does not modify user_cpu", user_cpu, U64L(29000));
+		ensure_equals("WCM t1 - isExpired() does not modify sys_cpu", sys_cpu, U64L(57000));
+	}
+}
+
+
+// Construct with zero horizon - not useful generally but will be useful in testing
+template<> template<>
+void deadmantimer_object_t::test<2>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(0.0, false);			// Zero is pre-expired
+		
+		ensure_equals("WOCM isExpired() still returns false with 0.0 time ctor()",
+					  timer.isExpired(0, started, stopped, count), false);
+	}
+
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(0.0, true);			// Zero is pre-expired
+		
+		ensure_equals("WCM isExpired() still returns false with 0.0 time ctor()",
+					  timer.isExpired(0, started, stopped, count, user_cpu, sys_cpu), false);
+	}
+}
+
+
+// "pre-expired" timer - starting a timer with a 0.0 horizon will result in
+// expiration on first test.
+template<> template<>
+void deadmantimer_object_t::test<3>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(0.0, false);
+
+		timer.start(0);
+		ensure_equals("WOCM isExpired() returns true with 0.0 horizon time",
+					  timer.isExpired(0, started, stopped, count), true);
+ 		ensure_approximately_equals("WOCM expired timer with no bell ringing has stopped == started", started, stopped, 8);
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(0.0, true);
+
+		timer.start(0);
+		ensure_equals("WCM isExpired() returns true with 0.0 horizon time",
+					  timer.isExpired(0, started, stopped, count, user_cpu, sys_cpu), true);
+		ensure_approximately_equals("WCM expired timer with no bell ringing has stopped == started", started, stopped, 8);
+	}
+}
+
+
+// "pre-expired" timer - bell rings are ignored as we're already expired.
+template<> template<>
+void deadmantimer_object_t::test<4>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(0.0, false);
+	
+		timer.start(0);
+		timer.ringBell(LLDeadmanTimer::getNow() + float_time_to_u64(1000.0), 1);
+		ensure_equals("WOCM isExpired() returns true with 0.0 horizon time after bell ring",
+					  timer.isExpired(0, started, stopped, count), true);
+		ensure_approximately_equals("WOCM ringBell has no impact on expired timer leaving stopped == started", started, stopped, 8);
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(0.0, true);
+	
+		timer.start(0);
+		timer.ringBell(LLDeadmanTimer::getNow() + float_time_to_u64(1000.0), 1);
+		ensure_equals("WCM isExpired() returns true with 0.0 horizon time after bell ring",
+					  timer.isExpired(0, started, stopped, count, user_cpu, sys_cpu), true);
+		ensure_approximately_equals("WCM ringBell has no impact on expired timer leaving stopped == started", started, stopped, 8);
+	}
+}
+
+
+// start(0) test - unexpired timer reports unexpired
+template<> template<>
+void deadmantimer_object_t::test<5>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(10.0, false);
+	
+		timer.start(0);
+		ensure_equals("WOCM isExpired() returns false after starting with 10.0 horizon time",
+					  timer.isExpired(0, started, stopped, count), false);
+		ensure_approximately_equals("WOCM t5 - isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WOCM t5 - isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WOCM t5 - isExpired() does not modify count", count, U64L(8));
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(10.0, true);
+	
+		timer.start(0);
+		ensure_equals("WCM isExpired() returns false after starting with 10.0 horizon time",
+					  timer.isExpired(0, started, stopped, count, user_cpu, sys_cpu), false);
+		ensure_approximately_equals("WCM t5 - isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WCM t5 - isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WCM t5 - isExpired() does not modify count", count, U64L(8));
+		ensure_equals("WCM t5 - isExpired() does not modify user_cpu", user_cpu, U64L(29000));
+		ensure_equals("WCM t5 - isExpired() does not modify sys_cpu", sys_cpu, U64L(57000));
+	}
+}
+
+
+// start() test - start in the past but not beyond 1 horizon
+template<> template<>
+void deadmantimer_object_t::test<6>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(10.0, false);
+
+		// Would like to do subtraction on current time but can't because
+		// the implementation on Windows is zero-based.  We wrap around
+		// the backside resulting in a large U64 number.
+	
+		LLDeadmanTimer::time_type the_past(LLDeadmanTimer::getNow());
+		LLDeadmanTimer::time_type now(the_past + float_time_to_u64(5.0));
+		timer.start(the_past);
+		ensure_equals("WOCM t6 - isExpired() returns false with 10.0 horizon time starting 5.0 in past",
+					  timer.isExpired(now, started, stopped, count), false);
+		ensure_approximately_equals("WOCM t6 - isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WOCM t6 - isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WOCM t6 - isExpired() does not modify count", count, U64L(8));
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(10.0, true);
+
+		// Would like to do subtraction on current time but can't because
+		// the implementation on Windows is zero-based.  We wrap around
+		// the backside resulting in a large U64 number.
+	
+		LLDeadmanTimer::time_type the_past(LLDeadmanTimer::getNow());
+		LLDeadmanTimer::time_type now(the_past + float_time_to_u64(5.0));
+		timer.start(the_past);
+		ensure_equals("WCM t6 - isExpired() returns false with 10.0 horizon time starting 5.0 in past",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+		ensure_approximately_equals("WCM t6 - isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WCM t6 - isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("t6 - isExpired() does not modify count", count, U64L(8));
+		ensure_equals("WCM t6 - isExpired() does not modify user_cpu", user_cpu, U64L(29000));
+		ensure_equals("WCM t6 - isExpired() does not modify sys_cpu", sys_cpu, U64L(57000));
+	}
+}
+
+
+// start() test - start in the past but well beyond 1 horizon
+template<> template<>
+void deadmantimer_object_t::test<7>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(10.0, false);
+		
+		// Would like to do subtraction on current time but can't because
+		// the implementation on Windows is zero-based.  We wrap around
+		// the backside resulting in a large U64 number.
+	
+		LLDeadmanTimer::time_type the_past(LLDeadmanTimer::getNow());
+		LLDeadmanTimer::time_type now(the_past + float_time_to_u64(20.0));
+		timer.start(the_past);
+		ensure_equals("WOCM t7 - isExpired() returns true with 10.0 horizon time starting 20.0 in past",
+					  timer.isExpired(now,started, stopped, count), true);
+		ensure_approximately_equals("WOCM t7 - starting before horizon still gives equal started / stopped", started, stopped, 8);
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(10.0, true);
+		
+		// Would like to do subtraction on current time but can't because
+		// the implementation on Windows is zero-based.  We wrap around
+		// the backside resulting in a large U64 number.
+	
+		LLDeadmanTimer::time_type the_past(LLDeadmanTimer::getNow());
+		LLDeadmanTimer::time_type now(the_past + float_time_to_u64(20.0));
+		timer.start(the_past);
+		ensure_equals("WCM t7 - isExpired() returns true with 10.0 horizon time starting 20.0 in past",
+					  timer.isExpired(now,started, stopped, count, user_cpu, sys_cpu), true);
+		ensure_approximately_equals("WOCM t7 - starting before horizon still gives equal started / stopped", started, stopped, 8);
+	}
+}
+
+
+// isExpired() test - results are read-once.  Probes after first true are false.
+template<> template<>
+void deadmantimer_object_t::test<8>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(10.0, false);
+
+		// Would like to do subtraction on current time but can't because
+		// the implementation on Windows is zero-based.  We wrap around
+		// the backside resulting in a large U64 number.
+	
+		LLDeadmanTimer::time_type the_past(LLDeadmanTimer::getNow());
+		LLDeadmanTimer::time_type now(the_past + float_time_to_u64(20.0));
+		timer.start(the_past);
+		ensure_equals("WOCM t8 - isExpired() returns true with 10.0 horizon time starting 20.0 in past",
+					  timer.isExpired(now, started, stopped, count), true);
+		
+		started = 42.0;
+		stopped = 97.0;
+		count = U64L(8);
+		ensure_equals("WOCM t8 - second isExpired() returns false after true",
+					  timer.isExpired(now, started, stopped, count), false);
+		ensure_approximately_equals("WOCM t8 - 2nd isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WOCM t8 - 2nd isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WOCM t8 - 2nd isExpired() does not modify count", count, U64L(8));
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(10.0, true);
+
+		// Would like to do subtraction on current time but can't because
+		// the implementation on Windows is zero-based.  We wrap around
+		// the backside resulting in a large U64 number.
+	
+		LLDeadmanTimer::time_type the_past(LLDeadmanTimer::getNow());
+		LLDeadmanTimer::time_type now(the_past + float_time_to_u64(20.0));
+		timer.start(the_past);
+		ensure_equals("WCM t8 - isExpired() returns true with 10.0 horizon time starting 20.0 in past",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), true);
+		
+		started = 42.0;
+		stopped = 97.0;
+		count = U64L(8);
+		user_cpu = 29000;
+		sys_cpu = 57000;
+		ensure_equals("WCM t8 - second isExpired() returns false after true",
+					  timer.isExpired(now, started, stopped, count), false);
+		ensure_approximately_equals("WCM t8 - 2nd isExpired() does not modify started", started, F64(42.0), 2);
+		ensure_approximately_equals("WCM t8 - 2nd isExpired() does not modify stopped", stopped, F64(97.0), 2);
+		ensure_equals("WCM t8 - 2nd isExpired() does not modify count", count, U64L(8));
+		ensure_equals("WCM t8 - 2nd isExpired() does not modify user_cpu", user_cpu, U64L(29000));
+		ensure_equals("WCM t8 - 2nd isExpired() does not modify sys_cpu", sys_cpu, U64L(57000));
+	}
+}
+
+
+// ringBell() test - see that we can keep a timer from expiring
+template<> template<>
+void deadmantimer_object_t::test<9>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(5.0, false);
+
+		LLDeadmanTimer::time_type now(LLDeadmanTimer::getNow());
+		F64 real_start(u64_time_to_float(now));
+		timer.start(0);
+
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		ensure_equals("WOCM t9 - 5.0 horizon timer has not timed out after 10 1-second bell rings",
+					  timer.isExpired(now, started, stopped, count), false);
+		F64 last_good_ring(u64_time_to_float(now));
+
+		// Jump forward and expire
+		now += float_time_to_u64(10.0);
+		ensure_equals("WOCM t9 - 5.0 horizon timer expires on 10-second jump",
+					  timer.isExpired(now, started, stopped, count), true);
+		ensure_approximately_equals("WOCM t9 - started matches start() time", started, real_start, 4);
+		ensure_approximately_equals("WOCM t9 - stopped matches last ringBell() time", stopped, last_good_ring, 4);
+		ensure_equals("WOCM t9 - 10 good ringBell()s", count, U64L(10));
+		ensure_equals("WOCM t9 - single read only", timer.isExpired(now, started, stopped, count), false);
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+		LLDeadmanTimer timer(5.0, true);
+
+		LLDeadmanTimer::time_type now(LLDeadmanTimer::getNow());
+		F64 real_start(u64_time_to_float(now));
+		timer.start(0);
+
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		ensure_equals("WCM t9 - 5.0 horizon timer has not timed out after 10 1-second bell rings",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+		F64 last_good_ring(u64_time_to_float(now));
+
+		// Jump forward and expire
+		now += float_time_to_u64(10.0);
+		ensure_equals("WCM t9 - 5.0 horizon timer expires on 10-second jump",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), true);
+		ensure_approximately_equals("WCM t9 - started matches start() time", started, real_start, 4);
+		ensure_approximately_equals("WCM t9 - stopped matches last ringBell() time", stopped, last_good_ring, 4);
+		ensure_equals("WCM t9 - 10 good ringBell()s", count, U64L(10));
+		ensure_equals("WCM t9 - single read only", timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+	}
+}
+
+
+// restart after expiration test - verify that restarts behave well
+template<> template<>
+void deadmantimer_object_t::test<10>()
+{
+	{
+		// Without cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8));
+		LLDeadmanTimer timer(5.0, false);
+
+		LLDeadmanTimer::time_type now(LLDeadmanTimer::getNow());
+		F64 real_start(u64_time_to_float(now));
+		timer.start(0);
+
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		ensure_equals("WOCM t10 - 5.0 horizon timer has not timed out after 10 1-second bell rings",
+					  timer.isExpired(now, started, stopped, count), false);
+		F64 last_good_ring(u64_time_to_float(now));
+
+		// Jump forward and expire
+		now += float_time_to_u64(10.0);
+		ensure_equals("WOCM t10 - 5.0 horizon timer expires on 10-second jump",
+					  timer.isExpired(now, started, stopped, count), true);
+		ensure_approximately_equals("WOCM t10 - started matches start() time", started, real_start, 4);
+		ensure_approximately_equals("WOCM t10 - stopped matches last ringBell() time", stopped, last_good_ring, 4);
+		ensure_equals("WOCM t10 - 10 good ringBell()s", count, U64L(10));
+		ensure_equals("WOCM t10 - single read only", timer.isExpired(now, started, stopped, count), false);
+		
+		// Jump forward and restart
+		now += float_time_to_u64(1.0);
+		real_start = u64_time_to_float(now);
+		timer.start(now);
+		
+		// Run a modified bell ring sequence
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		ensure_equals("WOCM t10 - 5.0 horizon timer has not timed out after 8 1-second bell rings",
+					  timer.isExpired(now, started, stopped, count), false);
+		last_good_ring = u64_time_to_float(now);
+
+		// Jump forward and expire
+		now += float_time_to_u64(10.0);
+		ensure_equals("WOCM t10 - 5.0 horizon timer expires on 8-second jump",
+					  timer.isExpired(now, started, stopped, count), true);
+		ensure_approximately_equals("WOCM t10 - 2nd started matches start() time", started, real_start, 4);
+		ensure_approximately_equals("WOCM t10 - 2nd stopped matches last ringBell() time", stopped, last_good_ring, 4);
+		ensure_equals("WOCM t10 - 8 good ringBell()s", count, U64L(8));
+		ensure_equals("WOCM t10 - single read only - 2nd start",
+					  timer.isExpired(now, started, stopped, count), false);
+	}
+	{
+		// With cpu metrics
+		F64 started(42.0), stopped(97.0);
+		U64 count(U64L(8)), user_cpu(29000), sys_cpu(57000);
+
+		LLDeadmanTimer timer(5.0, true);
+
+		LLDeadmanTimer::time_type now(LLDeadmanTimer::getNow());
+		F64 real_start(u64_time_to_float(now));
+		timer.start(0);
+
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		ensure_equals("WCM t10 - 5.0 horizon timer has not timed out after 10 1-second bell rings",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+		F64 last_good_ring(u64_time_to_float(now));
+
+		// Jump forward and expire
+		now += float_time_to_u64(10.0);
+		ensure_equals("WCM t10 - 5.0 horizon timer expires on 10-second jump",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), true);
+		ensure_approximately_equals("WCM t10 - started matches start() time", started, real_start, 4);
+		ensure_approximately_equals("WCM t10 - stopped matches last ringBell() time", stopped, last_good_ring, 4);
+		ensure_equals("WCM t10 - 10 good ringBell()s", count, U64L(10));
+		ensure_equals("WCM t10 - single read only", timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+		
+		// Jump forward and restart
+		now += float_time_to_u64(1.0);
+		real_start = u64_time_to_float(now);
+		timer.start(now);
+		
+		// Run a modified bell ring sequence
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		now += float_time_to_u64(1.0);
+		timer.ringBell(now, 1);
+		ensure_equals("WCM t10 - 5.0 horizon timer has not timed out after 8 1-second bell rings",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+		last_good_ring = u64_time_to_float(now);
+
+		// Jump forward and expire
+		now += float_time_to_u64(10.0);
+		ensure_equals("WCM t10 - 5.0 horizon timer expires on 8-second jump",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), true);
+		ensure_approximately_equals("WCM t10 - 2nd started matches start() time", started, real_start, 4);
+		ensure_approximately_equals("WCM t10 - 2nd stopped matches last ringBell() time", stopped, last_good_ring, 4);
+		ensure_equals("WCM t10 - 8 good ringBell()s", count, U64L(8));
+		ensure_equals("WCM t10 - single read only - 2nd start",
+					  timer.isExpired(now, started, stopped, count, user_cpu, sys_cpu), false);
+	}
+}
+
+
+
+} // end namespace tut
diff --git a/indra/llcommon/tests/llprocinfo_test.cpp b/indra/llcommon/tests/llprocinfo_test.cpp
new file mode 100644
index 0000000000..12d5a695ee
--- /dev/null
+++ b/indra/llcommon/tests/llprocinfo_test.cpp
@@ -0,0 +1,91 @@
+/** 
+ * @file llprocinfo_test.cpp
+ * @brief Tests for the LLProcInfo class.
+ *
+ * $LicenseInfo:firstyear=2013&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2013, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include "linden_common.h"
+
+#include "../llprocinfo.h"
+
+#include "../test/lltut.h"
+#include "../lltimer.h"
+
+
+static const LLProcInfo::time_type bad_user(289375U), bad_system(275U);
+
+
+namespace tut
+{
+
+struct procinfo_test
+{
+	procinfo_test()
+		{
+		}
+};
+
+typedef test_group<procinfo_test> procinfo_group_t;
+typedef procinfo_group_t::object procinfo_object_t;
+tut::procinfo_group_t procinfo_instance("LLProcInfo");
+
+
+// Basic invocation works
+template<> template<>
+void procinfo_object_t::test<1>()
+{
+	LLProcInfo::time_type user(bad_user), system(bad_system);
+
+	set_test_name("getCPUUsage() basic function");
+
+	LLProcInfo::getCPUUsage(user, system);
+	
+	ensure_not_equals("getCPUUsage() writes to its user argument", user, bad_user);
+	ensure_not_equals("getCPUUsage() writes to its system argument", system, bad_system);
+}
+
+
+// Time increases
+template<> template<>
+void procinfo_object_t::test<2>()
+{
+	LLProcInfo::time_type user(bad_user), system(bad_system);
+	LLProcInfo::time_type user2(bad_user), system2(bad_system);
+
+	set_test_name("getCPUUsage() increases over time");
+
+	LLProcInfo::getCPUUsage(user, system);
+	
+	for (int i(0); i < 100000; ++i)
+	{
+		ms_sleep(0);
+	}
+	
+	LLProcInfo::getCPUUsage(user2, system2);
+
+	ensure_equals("getCPUUsage() user value doesn't decrease over time", user2 >= user, true);
+	ensure_equals("getCPUUsage() system value doesn't decrease over time", system2 >= system, true);
+}
+
+
+} // end namespace tut
diff --git a/indra/llcorehttp/README.Linden b/indra/llcorehttp/README.Linden
new file mode 100644
index 0000000000..eb6ccab3bc
--- /dev/null
+++ b/indra/llcorehttp/README.Linden
@@ -0,0 +1,671 @@
+
+
+
+1.  HTTP Fetching in 15 Minutes
+
+    Let's start with a trivial working example.  You'll need a throwaway
+    build of the viewer.  And we'll use indra/newview/llappviewer.cpp as
+    the host module for these hacks.
+
+    First, add some headers:
+
+
+        #include "httpcommon.h"
+        #include "httprequest.h"
+        #include "httphandler.h"
+
+
+    You'll need to derive a class from HttpHandler (not HttpHandle).
+    This is used to deliver notifications of HTTP completion to your
+    code.  Place it near the top, before LLDeferredTaskList, say:
+
+
+        class MyHandler : public LLCore::HttpHandler
+        {
+        public:
+            MyHandler()
+            : LLCore::HttpHandler()
+            {}
+
+            virtual void onCompleted(LLCore::HttpHandle /* handle */,
+                                     LLCore::HttpResponse * /* response */)
+            {
+                LL_INFOS("Hack") << "It is happening again." << LL_ENDL;
+
+                delete this;    // Last statement
+            }
+        };
+
+
+    Add some statics up there as well:
+
+
+        // Our request object.  Allocate during initialiation.
+        static LLCore::HttpRequest * my_request(NULL);
+
+        // The policy class for HTTP traffic.
+        // Use HttpRequest::DEFAULT_POLICY_ID, but DO NOT SHIP WITH THIS VALUE!!
+        static LLCore::HttpRequest::policy_t my_policy(LLCore::HttpRequest::DEFAULT_POLICY_ID);
+
+        // Priority for HTTP requests.  Use 0U.
+        static LLCore::HttpRequest::priority_t my_priority(0U);
+
+
+    In LLAppViewer::init() after mAppCoreHttp.init(), create a request object:
+
+
+        my_request = new LLCore::HttpRequest();
+
+
+    In LLAppViewer::mainLoop(), just before entering the while loop,
+    we'll kick off one HTTP request:
+
+
+        // Construct a handler object (we'll use the heap this time):
+        MyHandler * my_handler = new MyHandler;
+
+        // Issue a GET request to 'http://www.example.com/' kicking off
+        // all the I/O, retry logic, etc.
+        LLCore::HttpHandle handle;
+        handle = my_request->requestGet(my_policy,
+                                        my_priority,
+                                        "http://www.example.com/",
+                                        NULL,
+                                        NULL,
+                                        my_handler);
+        if (LLCORE_HTTP_HANDLE_INVALID == handle)
+        {
+            LL_WARNS("Hack") << "Failed to launch HTTP request.  Try again."
+                             << LL_ENDL;
+        }
+
+
+    Finally, arrange to periodically call update() on the request object
+    to find out when the request completes.  This will be done by
+    calling the onCompleted() method with status information and
+    response data from the HTTP operation.  Add this to the
+    LLAppViewer::idle() method after the ping:
+
+
+        my_request->update(0);
+
+
+    That's it.  Build it, run it and watch the log file.  You should get
+    the "It is happening again." message indicating that the HTTP
+    operation completed in some manner.
+
+
+2.  What Does All That Mean
+
+    MyHandler/HttpHandler.  This class replaces the Responder-style in
+    legacy code.  One method is currently defined.  It is used for all
+    request completions, successful or failed:
+
+
+        void onCompleted(LLCore::HttpHandle /* handle */,
+                         LLCore::HttpResponse * /* response */);
+
+
+    The onCompleted() method is invoked as a callback during calls to
+    HttpRequest::update().  All I/O is completed asynchronously in
+    another thread.  But notifications are polled by calling update()
+    and invoking a handler for completed requests.
+
+    In this example, the invocation also deletes the handler (which is
+    never referenced by the llcorehttp code again).  But other
+    allocation models are possible including handlers shared by many
+    requests, stack-based handlers and handlers mixed in with other,
+    unrelated classes.
+
+    LLCore::HttpRequest().  Instances of this class are used to request
+    all major functions of the library.  Initialization, starting
+    requests, delivering final notification of completion and various
+    utility operations are all done via instances.  There is one very
+    important rule for instances:
+
+        Request objects may NOT be shared between threads.
+
+    my_priority.  The APIs support the idea of priority ordering of
+    requests but it hasn't been implemented and the hope is that this
+    will become useless and removed from the interface.  Use 0U except
+    as noted.
+
+    my_policy.  This is an important one.  This library attempts to
+    manage TCP connection usage more rigorously than in the past.  This
+    is done by issuing requests to a queue that has various settable
+    properties.  These establish connection usage for the queue as well
+    as how queues compete with one another.  (This is patterned after
+    class-based queueing used in various networking stacks.)  Several
+    classes are pre-defined.  Deciding when to use an existing class and
+    when to create a new one will determine what kind of experience
+    users have.  We'll pick up this question in detail below.
+
+    requestGet().  Issues an ordinary HTTP GET request to a given URL
+    and associating the request with a policy class, a priority and an
+    response handler.  Two additional arguments, not used here, allow
+    for additional headers on the request and for per-request options.
+    If successful, the call returns a handle whose value is other than
+    LLCORE_HTTP_HANDLE_INVALID.  The HTTP operation is then performed
+    asynchronously by another thread without any additional work by the
+    caller.  If the handle returned is invalid, you can get the status
+    code by calling my_request->getStatus().
+
+    update().  To get notification that the request has completed, a
+    call to update() will invoke onCompleted() methods.
+
+
+3.  Refinements, Necessary and Otherwise
+
+    MyHandler::onCompleted().  You'll want to do something useful with
+    your response.  Distinguish errors from successes and getting the
+    response body back in some form.
+
+    Add a new header:
+
+
+        #include "bufferarray.h"
+
+
+    Replace the existing MyHandler::onCompleted() definition with:
+
+
+        virtual void onCompleted(LLCore::HttpHandle /* handle */,
+                                 LLCore::HttpResponse * response)
+        {
+            LLCore::HttpStatus status = response->getStatus();
+            if (status)
+            {
+                // Successful request.  Try to fetch the data
+                LLCore::BufferArray * data = response->getBody();
+
+                if (data && data->size())
+                {
+                    // There's some data.  A BufferArray is a linked list
+                    // of buckets.  We'll create a linear buffer and copy
+                    // the data into it.
+                    size_t data_len = data->size();
+                    char * data_blob = new char [data_len + 1];
+                    data->read(0, data_blob, data_len);
+                    data_blob[data_len] = '\0';
+
+                    // Process the data now in NUL-terminated string.
+                    // Needs more scrubbing but this will do.
+                    LL_INFOS("Hack") << "Received:  " << data_blob << LL_ENDL;
+
+                    // Free the temporary data
+                    delete [] data_blob;
+                }
+            }
+            else
+            {
+                // Something went wrong.  Translate the status to
+                // a meaningful message.
+                LL_WARNS("Hack") << "HTTP GET failed.  Status:  "
+                                 << status.toTerseString()
+                                 << ", Reason:  " << status.toString()
+                                 << LL_ENDL;
+            }           
+
+            delete this;    // Last statement
+        }
+
+
+    HttpHeaders.  The header file "httprequest.h" documents the expected
+    important headers that will go out with the request.  You can add to
+    these by including an HttpHeaders object with the requestGet() call.
+    These are typically setup once as part of init rather than
+    dynamically created.
+
+    Add another header:
+
+
+        #include "httpheaders.h"
+
+
+    In LLAppViewer::mainLoop(), add this alongside the allocation of
+    my_handler:
+
+
+        // Additional headers for all requests
+        LLCore::HttpHeaders * my_headers = new LLCore::HttpHeaders();
+        my_headers->append("Accept", "text/html, application/llsd+xml");
+
+
+    HttpOptions.  Options are similar and include a mix of value types.
+    One interesting per-request option is the trace setting.  This
+    enables various debug-type messages in the log file that show the
+    progress of the request through the library.  It takes values from
+    zero to three with higher values giving more verbose logging.  We'll
+    use '2' and this will also give us a chance to verify that
+    HttpHeaders works as expected.
+
+    Same as above, a new header:
+
+
+        #include "httpoptions.h"
+
+
+    And in LLAppView::mainLoop():
+
+
+        // Special options for requests
+        LLCore::HttpOptions * my_options = new LLCore::HttpOptions();
+        my_options->setTrace(2);
+
+
+    Now let's put that all together into a more complete requesting
+    sequence.  Replace the existing invocation of requestGet() with this
+    slightly more elaborate block:
+
+
+        LLCore::HttpHandle handle;
+        handle = my_request->requestGet(my_policy,
+                                        my_priority,
+                                        "http://www.example.com/",
+                                        my_options,
+                                        my_headers,
+                                        my_handler);
+        if (LLCORE_HTTP_HANDLE_INVALID == handle)
+        {
+             LLCore::HttpStatus status = my_request->getStatus();
+
+             LL_WARNS("Hack") << "Failed to request HTTP GET.  Status:  "
+                              << status.toTerseString()
+                              << ", Reason:  " << status.toString()
+                              << LL_ENDL;
+
+             delete my_handler;    // No longer needed.
+             my_handler = NULL;
+        }
+
+
+    Build, run and examine the log file.  You'll get some new data with
+    this run.  First, you should get the www.example.com home page
+    content:
+
+
+----------------------------------------------------------------------------
+2013-09-17T20:26:51Z INFO: MyHandler::onCompleted: Received:  <!doctype html>
+<html>
+<head>
+    <title>Example Domain</title>
+
+    <meta charset="utf-8" />
+    <meta http-equiv="Content-type" content="text/html; charset=utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <style type="text/css">
+    body {
+        background-color: #f0f0f2;
+        margin: 0;
+        padding: 0;
+        font-family: "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
+        
+    }
+    div {
+        width: 600px;
+        margin: 5em auto;
+        padding: 50px;
+        background-color: #fff;
+        border-radius: 1em;
+    }
+    a:link, a:visited {
+        color: #38488f;
+        text-decoration: none;
+    }
+    @media (max-width: 700px) {
+        body {
+            background-color: #fff;
+        }
+        div {
+            width: auto;
+            margin: 0 auto;
+            border-radius: 0;
+            padding: 1em;
+        }
+    }
+    </style>    
+</head>
+
+<body>
+<div>
+    <h1>Example Domain</h1>
+    <p>This domain is established to be used for illustrative examples in documents. You may use this
+    domain in examples without prior coordination or asking for permission.</p>
+    <p><a href="http://www.iana.org/domains/example">More information...</a></p>
+</div>
+</body>
+</html>
+----------------------------------------------------------------------------
+
+
+    You'll also get a detailed trace of the HTTP operation itself.  Note
+    the HEADEROUT line which shows the additional header added to the
+    request.
+
+
+----------------------------------------------------------------------------
+HttpService::processRequestQueue: TRACE, FromRequestQueue, Handle:  086D3148
+HttpLibcurl::addOp: TRACE, ToActiveQueue, Handle:  086D3148, Actives:  0, Readies:  0
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  TEXT, Data:  About to connect() to www.example.com port 80 (#0) 
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  TEXT, Data:    Trying 93.184.216.119... 
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  TEXT, Data:  Connected to www.example.com (93.184.216.119) port 80 (#0) 
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  TEXT, Data:  Connected to www.example.com (93.184.216.119) port 80 (#0) 
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADEROUT, Data:  GET / HTTP/1.1  Host: www.example.com  Accept-Encoding: deflate, gzip  Connection: keep-alive  Keep-alive: 300  Accept: text/html, application/llsd+xml
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  HTTP/1.1 200 OK  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Accept-Ranges: bytes  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Cache-Control: max-age=604800  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Content-Type: text/html  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Date: Tue, 17 Sep 2013 20:26:56 GMT  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Etag: "3012602696"  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Expires: Tue, 24 Sep 2013 20:26:56 GMT  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Last-Modified: Fri, 09 Aug 2013 23:54:35 GMT  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Server: ECS (ewr/1590)  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  X-Cache: HIT  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  x-ec-custom-error: 1  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:  Content-Length: 1270  
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  HEADERIN, Data:    
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  DATAIN, Data:  256 Bytes
+HttpOpRequest::debugCallback: TRACE, LibcurlDebug, Handle:  086D3148, Type:  TEXT, Data:  Connection #0 to host www.example.com left intact 
+HttpLibcurl::completeRequest: TRACE, RequestComplete, Handle:  086D3148, Status:  Http_200
+HttpOperation::addAsReply: TRACE, ToReplyQueue, Handle:  086D3148
+----------------------------------------------------------------------------
+
+
+4.  What Does All That Mean, Part 2
+
+    HttpStatus.  The HttpStatus object encodes errors from libcurl, the
+    library itself and HTTP status values.  It does this to avoid
+    collapsing all non-HTTP error into a single '499' HTTP status and to
+    make errors distinct.
+
+    To aid programming, the usual bool conversions are available so that
+    you can write 'if (status)' and the expected thing will happen
+    whether it's an HTTP, libcurl or library error.  There's also
+    provision to override the treatment of HTTP errors (making 404 a
+    success, say).
+
+    Share data, don't copy it.  The library was started with the goal of
+    avoiding data copies as much as possible.  Instead, read-only data
+    sharing across threads with atomic reference counts is used for a
+    number of data types.  These currently are:
+
+        * BufferArray.  Linked list of data blocks/HTTP bodies.
+        * HttpHeaders.  Shared headers for both requests and responses.
+        * HttpOptions.  Request-only data modifying HTTP behavior.
+        * HttpResponse.  HTTP response description given to onCompleted.
+
+    Using objects of these types requires a few rules:
+
+        * Constructor always gives a reference to caller.
+        * References are dropped with release() not delete.
+        * Additional references may be taken out with addRef().
+        * Unless otherwise stated, once an object is shared with another
+          thread it should be treated as read-only.  There's no
+          synchronization on the objects themselves.
+
+    HttpResponse.  You'll encounter this mainly in onCompleted() methods.
+    Commonly-used interfaces on this object:
+
+        * getStatus() to return the final status of the request.
+        * getBody() to retrieve the response body which may be NULL or
+          zero-length.
+        * getContentType() to return the value of the 'Content-Type'
+          header or an empty string if none was sent.
+
+    This is a reference-counted object so you can call addRef() on it
+    and hold onto the response for an arbitrary time.  But you'll
+    usually just call a few methods and return from onCompleted() whose
+    caller will release the object.
+
+    BufferArray.  The core data representation for request and response
+    bodies.  In HTTP responses, it's fetched with the getBody() method
+    and may be NULL or non-NULL with zero length.  All successful data
+    handling should check both conditions before attempting to fetch
+    data from the object.  Data access model uses simple read/write
+    semantics:
+
+        * append()
+        * size()
+        * read()
+        * write()
+
+    (There is a more sophisticated stream adapter that extends these
+    methods and will be covered below.)  So, one way to retrieve data
+    from a request is as follows:
+
+
+        LLCore::BufferArray * data = response->getBody();
+        if (data && data->size())
+        {
+            size_t data_len = data->size();
+            char * data_blob = new char [data_len + 1];
+            data->read(0, data_blob, data_len);
+
+
+    HttpOptions and HttpResponse.  Really just simple containers of POD
+    and std::string pairs.  But reference counted and the rule about not
+    modifying after sharing must be followed.  You'll have the urge to
+    change options dynamically at some point.  And you'll try to do that
+    by just writing new values to the shared object.  And in tests
+    everything will appear to work.  Then you ship and people in the
+    real world start hitting read/write races in strings and then crash.
+    Don't be lazy.
+
+    HttpHandle.  Uniquely identifies a request and can be used to
+    identify it in an onCompleted() method or cancel it if it's still
+    queued.  But as soon as a request's onCompleted() invocation
+    returns, the handle becomes invalid and may be reused immediately
+    for new requests.  Don't hold on to handles after notification.
+
+
+5.  And Still More Refinements
+
+    (Note: The following refinements are just code fragments.  They
+    don't directly fit into the working example above.  But they
+    demonstrate several idioms you'll want to copy.)
+
+    LLSD, std::streambuf, std::iostream.  The read(), write() and
+    append() methods may be adequate for your purposes.  But we use a
+    lot of LLSD.  Its interfaces aren't particularly compatible with
+    BufferArray.  And so two adapters are available to give
+    stream-like behaviors:  BufferArrayStreamBuf and BufferArrayStream,
+    which implement the std::streambuf and std::iostream interfaces,
+    respectively.
+
+    A std::streambuf interface isn't something you'll want to use
+    directly.  Instead, you'll use the much friendlier std::iostream
+    interface found in BufferArrayStream.  This adapter gives you all
+    the '>>' and '<<' operators you'll want as well as working
+    directly with the LLSD conversion operators.
+
+    Some new headers:
+
+
+        #include "bufferstream.h"
+        #include "llsdserialize.h"
+
+
+    And an updated fragment based on onCompleted() above:
+
+
+                // Successful request.  Try to fetch the data
+                LLCore::BufferArray * data = response->getBody();
+                LLSD resp_llsd;
+
+                if (data && data->size())
+                {
+                    // There's some data and we expect this to be
+                    // LLSD.  Checking of content type and validation
+                    // during parsing would be admirable additions.
+                    // But we'll forgo that now.
+                    LLCore::BufferArrayStream data_stream(data);
+                    LLSDSerialize::fromXML(resp_llsd, data_stream);
+                }
+                LL_INFOS("Hack") << "LLSD Received:  " << resp_llsd << LL_ENDL;
+            }
+            else
+            {
+
+
+    Converting an LLSD object into an XML stream stored in a
+    BufferArray is just the reverse of the above:
+
+
+        BufferArray * data = new BufferArray();
+        LLCore::BufferArrayStream data_stream(data);
+
+        LLSD src_llsd;
+        src_llsd["foo"] = "bar";
+
+        LLSDSerialize::toXML(src_llsd, data_stream);
+
+        // 'data' now contains an XML payload and can be sent
+        // to a web service using the requestPut() or requestPost()
+        //  methods.
+        ...  requestPost(...);
+
+        // And don't forget to release the BufferArray.
+        data->release();
+        data = NULL;
+
+
+    LLSD will often go hand-in-hand with BufferArray and data
+    transport.  But you can also do all the streaming I/O you'd expect
+    of a std::iostream object:
+
+
+        BufferArray * data = new BufferArray();
+        LLCore::BufferArrayStream data_stream(data);
+
+        data_stream << "Hello, World!" << 29.4 << '\n';
+        std::string str;
+        data_stream >> str;
+        std::cout << str << std::endl;
+
+        data->release();
+        // Actual delete will occur when 'data_stream'
+        // falls out of scope and is destructed.
+
+
+    Scoping objects and cleaning up.  The examples haven't bothered
+    with cleanup of objects that are no longer needed.  Instead, most
+    objects have been allocated as if they were global and eternal.
+    You'll put the objects in more appropriate feature objects and
+    clean them up as a group.  Here's a checklist for actions you may
+    need to take on cleanup:
+
+    * Call delete on:
+      o HttpHandlers created on the heap
+      o HttpRequest objects
+    * Call release() on:
+      o BufferArray objects
+      o HttpHeaders objects
+      o HttpOptions objects
+      o HttpResponse objects
+
+    On program exit, as threads wind down, the library continues to
+    operate safely.  Threads don't interact via the library and even
+    dangling references to HttpHandler objects are safe.  If you don't
+    call HttpRequest::update(), handler references are never
+    dereferenced.
+
+    You can take a more thorough approach to wind-down.  Keep a list
+    of HttpHandles (not HttpHandlers) of outstanding requests.  For
+    each of these, call HttpRequest::requestCancel() to cancel the
+    operation.  (Don't add the cancel requests' handled to the list.)
+    This will cancel the outstanding requests that haven't completed.
+    Canceled or completed, all requests will queue notifications.  You
+    can now cycle calling update() discarding responses.  Continue
+    until all requests notify or a few seconds have passed.
+
+    Global startup and shutdown is handled in the viewer.  But you can
+    learn about it in the code or in the documentation in the headers.
+
+
+6.  Choosing a Policy Class
+
+    Now it's time to get rid of the default policy class.  Take a look
+    at the policy class definitions in newview/llappcorehttp.h.
+    Ideally, you'll find one that's compatible with what you're doing.
+    Some of the compatibility guidelines are:
+
+    * Destination: Pair of host and port.  Mixing requests with
+      different destinations may cause more connection setup and tear
+      down.
+
+    * Method: http or https.  Usually moot given destination.  But
+      mixing these may also cause connection churn.
+
+    * Transfer size: If you're moving 100MB at a time and you make your
+      requests to the same policy class as a lot of small, fast event
+      information that fast traffic is going to get stuck behind you
+      and someone's experience is going to be miserable.
+
+    * Long poll requests: These are long-lived, must- do operations.
+      They have a special home called AP_LONG_POLL.
+
+    * Concurrency: High concurrency (5 or more) and large transfer
+      sizes are incompatible.  Another head-of-the-line problem.  High
+      concurrency is tolerated when it's desired to get maximal
+      throughput.  Mesh and texture downloads, for example.
+
+    * Pipelined: If your requests are not idempotent, stay away from
+      anything marked 'soon' or 'yes'.  Hidden retries may be a
+      problem for you.  For now, would also recommend keeping PUT and
+      POST requests out of classes that may be pipelined.  Support for
+      that is still a bit new.
+
+    If you haven't found a compatible match, you can either create a
+    new class (llappcorehttp.*) or just use AP_DEFAULT, the catchall
+    class when all else fails.  Inventory query operations might be a
+    candidate for a new class that supported pipelining on https:.
+    Same with display name lookups and other bursty-at-login
+    operations.  For other things, AP_DEFAULT will do what it can and
+    will, in some way or another, tolerate any usage.  Whether the
+    users' experiences are good are for you to determine.
+
+    
+7.  FAQ
+
+    Q1.  What do these policy classes achieve?
+
+    A1.  Previously, HTTP-using code in the viewer was written as if
+    it were some isolated, local operation that didn't have to
+    consider resources, contention or impact on services and the
+    larger environment.  The result was an application with on the
+    order of 100 HTTP launch points in its codebase that could create
+    dozens or even 100's of TCP connections zeroing in on grid
+    services and disrupting networking equipment, web services and
+    innocent users.  The use of policy classes (modeled on
+    http://en.wikipedia.org/wiki/Class-based_queueing) is a means to
+    restrict connection concurrency, good and necessary in itself.  In
+    turn, that reduces demands on an expensive resource (connection
+    setup and concurrency) which relieves strain on network points.
+    That enables connection keepalive and opportunites for true
+    improvements in throughput and user experience.
+
+    Another aspect of the classes is that they give some control over
+    how competing demands for the network will be apportioned.  If
+    mesh fetches, texture fetches and inventory queries are all being
+    made at once, the relative weights of their classes' concurrency
+    limits established that apportioning.  We now have an opportunity
+    to balance the entire viewer system.
+
+    Q2.  How's that data sharing with refcounts working for you?
+
+    A2.  Meh.  It does reduce memory churn and the frequency at which
+    free blocks must be moved between threads.  But it's also a design
+    for static configuration and dynamic reconfiguration (not
+    requiring a restart) is favored.  Creating new options for every
+    request isn't too bad, it a sequence of "new, fill, request,
+    release" for each requested operation.  That in contrast to doing
+    the "new, fill, release" at startup.  The bad comes in getting at
+    the source data.  One rule in this work was "no new thread
+    problems."  And one source for those is pulling setting values out
+    of gSettings in threads.  None of that is thread safe though we
+    tend to get away with it.
+
+    Q3.  What needs to be done?
+
+    A3.  There's a To-Do list in _httpinternal.h.  It has both large
+    and small projects here if someone would like to try changes.
diff --git a/indra/llcorehttp/_httpinternal.h b/indra/llcorehttp/_httpinternal.h
index 008e4fd95c..f80d7f60f5 100755
--- a/indra/llcorehttp/_httpinternal.h
+++ b/indra/llcorehttp/_httpinternal.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -36,7 +36,8 @@
 // General library to-do list
 //
 // - Implement policy classes.  Structure is mostly there just didn't
-//   need it for the first consumer.
+//   need it for the first consumer.  [Classes are there.  More
+//   advanced features, like borrowing, aren't there yet.]
 // - Consider Removing 'priority' from the request interface.  Its use
 //   in an always active class can lead to starvation of low-priority
 //   requests.  Requires coodination of priority values across all
@@ -46,6 +47,7 @@
 //   may not really need it.
 // - Set/get for global policy and policy classes is clumsy.  Rework
 //   it heading in a direction that allows for more dynamic behavior.
+//   [Mostly fixed]
 // - Move HttpOpRequest::prepareRequest() to HttpLibcurl for the
 //   pedantic.
 // - Update downloader and other long-duration services are going to
@@ -64,6 +66,12 @@
 //   This won't help in the face of the router problems we've looked
 //   at, however.  Detect starvation due to UDP activity and provide
 //   feedback to it.
+// - Change the transfer timeout scheme.  We're less interested in
+//   absolute time, in most cases, than in continuous progress.
+// - Many of the policy class settings are currently applied to the
+//   entire class.  Some, like connection limits, would be better
+//   applied to each destination target making multiple targets
+//   independent.
 //
 // Integration to-do list
 // - LLTextureFetch still needs a major refactor.  The use of
@@ -73,7 +81,6 @@
 //   the main source file.
 // - Expand areas of usage eventually leading to the removal of LLCurl.
 //   Rough order of expansion:
-//   .  Mesh fetch
 //   .  Avatar names
 //   .  Group membership lists
 //   .  Caps access in general
@@ -97,8 +104,8 @@ namespace LLCore
 {
 
 // Maxium number of policy classes that can be defined.
-// *TODO:  Currently limited to the default class, extend.
-const int HTTP_POLICY_CLASS_LIMIT = 1;
+// *TODO:  Currently limited to the default class + 1, extend.
+const int HTTP_POLICY_CLASS_LIMIT = 8;
 
 // Debug/informational tracing.  Used both
 // as a global option and in per-request traces.
@@ -129,6 +136,7 @@ const int HTTP_REDIRECTS_DEFAULT = 10;
 // Retries and time-on-queue are not included and aren't
 // accounted for.
 const long HTTP_REQUEST_TIMEOUT_DEFAULT = 30L;
+const long HTTP_REQUEST_XFER_TIMEOUT_DEFAULT = 0L;
 const long HTTP_REQUEST_TIMEOUT_MIN = 0L;
 const long HTTP_REQUEST_TIMEOUT_MAX = 3600L;
 
@@ -137,6 +145,11 @@ const int HTTP_CONNECTION_LIMIT_DEFAULT = 8;
 const int HTTP_CONNECTION_LIMIT_MIN = 1;
 const int HTTP_CONNECTION_LIMIT_MAX = 256;
 
+// Miscellaneous defaults
+const long HTTP_PIPELINING_DEFAULT = 0L;
+const bool HTTP_USE_RETRY_AFTER_DEFAULT = true;
+const long HTTP_THROTTLE_RATE_DEFAULT = 0L;
+
 // Tuning parameters
 
 // Time worker thread sleeps after a pass through the
diff --git a/indra/llcorehttp/_httplibcurl.cpp b/indra/llcorehttp/_httplibcurl.cpp
index d49f615ac4..e56bc84174 100755
--- a/indra/llcorehttp/_httplibcurl.cpp
+++ b/indra/llcorehttp/_httplibcurl.cpp
@@ -41,7 +41,8 @@ namespace LLCore
 HttpLibcurl::HttpLibcurl(HttpService * service)
 	: mService(service),
 	  mPolicyCount(0),
-	  mMultiHandles(NULL)
+	  mMultiHandles(NULL),
+	  mActiveHandles(NULL)
 {}
 
 
@@ -77,6 +78,9 @@ void HttpLibcurl::shutdown()
 
 		delete [] mMultiHandles;
 		mMultiHandles = NULL;
+
+		delete [] mActiveHandles;
+		mActiveHandles = NULL;
 	}
 
 	mPolicyCount = 0;
@@ -90,9 +94,12 @@ void HttpLibcurl::start(int policy_count)
 	
 	mPolicyCount = policy_count;
 	mMultiHandles = new CURLM * [mPolicyCount];
+	mActiveHandles = new int [mPolicyCount];
+	
 	for (int policy_class(0); policy_class < mPolicyCount; ++policy_class)
 	{
 		mMultiHandles[policy_class] = curl_multi_init();
+		mActiveHandles[policy_class] = 0;
 	}
 }
 
@@ -110,8 +117,10 @@ HttpService::ELoopSpeed HttpLibcurl::processTransport()
 	// Give libcurl some cycles to do I/O & callbacks
 	for (int policy_class(0); policy_class < mPolicyCount; ++policy_class)
 	{
-		if (! mMultiHandles[policy_class])
+		if (! mActiveHandles[policy_class] || ! mMultiHandles[policy_class])
+		{
 			continue;
+		}
 		
 		int running(0);
 		CURLMcode status(CURLM_CALL_MULTI_PERFORM);
@@ -132,12 +141,10 @@ HttpService::ELoopSpeed HttpLibcurl::processTransport()
 				CURL * handle(msg->easy_handle);
 				CURLcode result(msg->data.result);
 
-				if (completeRequest(mMultiHandles[policy_class], handle, result))
-				{
-					// Request is still active, don't get too sleepy
-					ret = HttpService::NORMAL;
-				}
-				handle = NULL;			// No longer valid on return
+				completeRequest(mMultiHandles[policy_class], handle, result);
+				handle = NULL;					// No longer valid on return
+				ret = HttpService::NORMAL;		// If anything completes, we may have a free slot.
+												// Turning around quickly reduces connection gap by 7-10mS.
 			}
 			else if (CURLMSG_NONE == msg->msg)
 			{
@@ -193,6 +200,7 @@ void HttpLibcurl::addOp(HttpOpRequest * op)
 	
 	// On success, make operation active
 	mActiveOps.insert(op);
+	++mActiveHandles[op->mReqPolicy];
 }
 
 
@@ -214,6 +222,7 @@ bool HttpLibcurl::cancel(HttpHandle handle)
 
 	// Drop references
 	mActiveOps.erase(it);
+	--mActiveHandles[op->mReqPolicy];
 	op->release();
 
 	return true;
@@ -240,7 +249,7 @@ void HttpLibcurl::cancelRequest(HttpOpRequest * op)
 	{
 		LL_INFOS("CoreHttp") << "TRACE, RequestCanceled, Handle:  "
 							 << static_cast<HttpHandle>(op)
-							 << ", Status:  " << op->mStatus.toHex()
+							 << ", Status:  " << op->mStatus.toTerseString()
 							 << LL_ENDL;
 	}
 
@@ -275,6 +284,7 @@ bool HttpLibcurl::completeRequest(CURLM * multi_handle, CURL * handle, CURLcode
 
 	// Deactivate request
 	mActiveOps.erase(it);
+	--mActiveHandles[op->mReqPolicy];
 	op->mCurlActive = false;
 
 	// Set final status of request if it hasn't failed by other mechanisms yet
@@ -316,7 +326,7 @@ bool HttpLibcurl::completeRequest(CURLM * multi_handle, CURL * handle, CURLcode
 	{
 		LL_INFOS("CoreHttp") << "TRACE, RequestComplete, Handle:  "
 							 << static_cast<HttpHandle>(op)
-							 << ", Status:  " << op->mStatus.toHex()
+							 << ", Status:  " << op->mStatus.toTerseString()
 							 << LL_ENDL;
 	}
 
@@ -336,19 +346,9 @@ int HttpLibcurl::getActiveCount() const
 
 int HttpLibcurl::getActiveCountInClass(int policy_class) const
 {
-	int count(0);
-	
-	for (active_set_t::const_iterator iter(mActiveOps.begin());
-		 mActiveOps.end() != iter;
-		 ++iter)
-	{
-		if ((*iter)->mReqPolicy == policy_class)
-		{
-			++count;
-		}
-	}
-	
-	return count;
+	llassert_always(policy_class < mPolicyCount);
+
+	return mActiveHandles ? mActiveHandles[policy_class] : 0;
 }
 
 
diff --git a/indra/llcorehttp/_httplibcurl.h b/indra/llcorehttp/_httplibcurl.h
index 611f029ef5..67f98dd4f0 100755
--- a/indra/llcorehttp/_httplibcurl.h
+++ b/indra/llcorehttp/_httplibcurl.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -71,16 +71,22 @@ public:
 	///
 	/// @return			Indication of how long this method is
 	///					willing to wait for next service call.
+	///
+	/// Threading:  called by worker thread.
 	HttpService::ELoopSpeed processTransport();
 
 	/// Add request to the active list.  Caller is expected to have
 	/// provided us with a reference count on the op to hold the
 	/// request.  (No additional references will be added.)
+	///
+	/// Threading:  called by worker thread.
 	void addOp(HttpOpRequest * op);
 
 	/// One-time call to set the number of policy classes to be
 	/// serviced and to create the resources for each.  Value
 	/// must agree with HttpPolicy::setPolicies() call.
+	///
+	/// Threading:  called by init thread.
 	void start(int policy_count);
 
 	/// Synchronously stop libcurl operations.  All active requests
@@ -91,9 +97,13 @@ public:
 	/// respective reply queues.
 	///
 	/// Can be restarted with a start() call.
+	///
+	/// Threading:  called by worker thread.
 	void shutdown();
 
 	/// Return global and per-class counts of active requests.
+	///
+	/// Threading:  called by worker thread.
 	int getActiveCount() const;
 	int getActiveCountInClass(int policy_class) const;
 
@@ -103,6 +113,7 @@ public:
 	///
 	/// @return			True if handle was found and operation canceled.
 	///
+	/// Threading:  called by worker thread.
 	bool cancel(HttpHandle handle);
 
 protected:
@@ -121,7 +132,8 @@ protected:
 	HttpService *		mService;				// Simple reference, not owner
 	active_set_t		mActiveOps;
 	int					mPolicyCount;
-	CURLM **			mMultiHandles;
+	CURLM **			mMultiHandles;			// One handle per policy class
+	int *				mActiveHandles;			// Active count per policy class
 }; // end class HttpLibcurl
 
 }  // end namespace LLCore
diff --git a/indra/llcorehttp/_httpoperation.cpp b/indra/llcorehttp/_httpoperation.cpp
index 5cf5bc5930..5bb0654652 100755
--- a/indra/llcorehttp/_httpoperation.cpp
+++ b/indra/llcorehttp/_httpoperation.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -53,7 +53,7 @@ HttpOperation::HttpOperation()
 	  mUserHandler(NULL),
 	  mReqPolicy(HttpRequest::DEFAULT_POLICY_ID),
 	  mReqPriority(0U),
-	  mTracing(0)
+	  mTracing(HTTP_TRACE_OFF)
 {
 	mMetricCreated = totalTime();
 }
@@ -94,7 +94,7 @@ void HttpOperation::stageFromRequest(HttpService *)
 	// Default implementation should never be called.  This
 	// indicates an operation making a transition that isn't
 	// defined.
-	LL_ERRS("HttpCore") << "Default stageFromRequest method may not be called."
+	LL_ERRS("CoreHttp") << "Default stageFromRequest method may not be called."
 						<< LL_ENDL;
 }
 
@@ -104,7 +104,7 @@ void HttpOperation::stageFromReady(HttpService *)
 	// Default implementation should never be called.  This
 	// indicates an operation making a transition that isn't
 	// defined.
-	LL_ERRS("HttpCore") << "Default stageFromReady method may not be called."
+	LL_ERRS("CoreHttp") << "Default stageFromReady method may not be called."
 						<< LL_ENDL;
 }
 
@@ -114,7 +114,7 @@ void HttpOperation::stageFromActive(HttpService *)
 	// Default implementation should never be called.  This
 	// indicates an operation making a transition that isn't
 	// defined.
-	LL_ERRS("HttpCore") << "Default stageFromActive method may not be called."
+	LL_ERRS("CoreHttp") << "Default stageFromActive method may not be called."
 						<< LL_ENDL;
 }
 
diff --git a/indra/llcorehttp/_httpoperation.h b/indra/llcorehttp/_httpoperation.h
index 914627fad0..937a61187d 100755
--- a/indra/llcorehttp/_httpoperation.h
+++ b/indra/llcorehttp/_httpoperation.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -72,7 +72,7 @@ class HttpService;
 class HttpOperation : public LLCoreInt::RefCounted
 {
 public:
-	/// Threading:  called by a consumer/application thread.
+	/// Threading:  called by consumer thread.
 	HttpOperation();
 
 protected:
@@ -108,7 +108,7 @@ public:
 	///							by the worker thread.  This is passible data
 	///							until notification is performed.
 	///
-	/// Threading:  called by application thread.
+	/// Threading:  called by consumer thread.
 	///
 	void setReplyPath(HttpReplyQueue * reply_queue,
 					  HttpHandler * handler);
@@ -141,7 +141,7 @@ public:
 	/// call to HttpRequest::update().  This method does the necessary
 	/// dispatching.
 	///
-	/// Threading:  called by application thread.
+	/// Threading:  called by consumer thread.
 	///
 	virtual void visitNotifier(HttpRequest *);
 
diff --git a/indra/llcorehttp/_httpoprequest.cpp b/indra/llcorehttp/_httpoprequest.cpp
index d8057364c4..43dd069bc6 100755
--- a/indra/llcorehttp/_httpoprequest.cpp
+++ b/indra/llcorehttp/_httpoprequest.cpp
@@ -64,6 +64,15 @@ int parse_content_range_header(char * buffer,
 							   unsigned int * last,
 							   unsigned int * length);
 
+// Similar for Retry-After headers.  Only parses the delta form
+// of the header, HTTP time formats aren't interesting for client
+// purposes.
+//
+// @return		0 if successfully parsed and seconds time delta
+//				returned in time argument.
+//
+int parse_retry_after_header(char * buffer, int * time);
+
 
 // Take data from libcurl's CURLOPT_DEBUGFUNCTION callback and
 // escape and format it for a tracing line in logging.  Absolutely
@@ -74,14 +83,16 @@ void escape_libcurl_debug_data(char * buffer, size_t len, bool scrub,
 							   std::string & safe_line);
 
 
-// OS-neutral string comparisons of various types
-int os_strncasecmp(const char *s1, const char *s2, size_t n);
-int os_strcasecmp(const char *s1, const char *s2);
-char * os_strtok_r(char *str, const char *delim, char **saveptr);
-
+// OS-neutral string comparisons of various types.
+int os_strcasecmp(const char * s1, const char * s2);
+char * os_strtok_r(char * str, const char * delim, char ** saveptr);
+char * os_strtrim(char * str);
+char * os_strltrim(char * str);
+void os_strlower(char * str);
 
-static const char * const hdr_whitespace(" \t");
-static const char * const hdr_separator(": \t");
+// Error testing and reporting for libcurl status codes
+void check_curl_easy_code(CURLcode code);
+void check_curl_easy_code(CURLcode code, int curl_setopt_option);
 
 } // end anonymous namespace
 
@@ -104,12 +115,15 @@ HttpOpRequest::HttpOpRequest()
 	  mCurlService(NULL),
 	  mCurlHeaders(NULL),
 	  mCurlBodyPos(0),
+	  mCurlTemp(NULL),
+	  mCurlTempLen(0),
 	  mReplyBody(NULL),
 	  mReplyOffset(0),
 	  mReplyLength(0),
 	  mReplyFullLength(0),
 	  mReplyHeaders(NULL),
 	  mPolicyRetries(0),
+	  mPolicy503Retries(0),
 	  mPolicyRetryAt(HttpTime(0)),
 	  mPolicyRetryLimit(HTTP_RETRY_COUNT_DEFAULT)
 {
@@ -153,6 +167,10 @@ HttpOpRequest::~HttpOpRequest()
 		mCurlHeaders = NULL;
 	}
 
+	delete [] mCurlTemp;
+	mCurlTemp = NULL;
+	mCurlTempLen = 0;
+	
 	if (mReplyBody)
 	{
 		mReplyBody->release();
@@ -208,6 +226,11 @@ void HttpOpRequest::stageFromActive(HttpService * service)
 		mCurlHeaders = NULL;
 	}
 
+	// Also not needed on the other side
+	delete [] mCurlTemp;
+	mCurlTemp = NULL;
+	mCurlTempLen = 0;
+	
 	addAsReply();
 }
 
@@ -226,6 +249,7 @@ void HttpOpRequest::visitNotifier(HttpRequest * request)
 			response->setRange(mReplyOffset, mReplyLength, mReplyFullLength);
 		}
 		response->setContentType(mReplyConType);
+		response->setRetries(mPolicyRetries, mPolicy503Retries);
 		
 		mUserHandler->onCompleted(static_cast<HttpHandle>(this), response);
 
@@ -335,6 +359,10 @@ void HttpOpRequest::setupCommon(HttpRequest::policy_t policy_id,
 		{
 			mProcFlags |= PF_SAVE_HEADERS;
 		}
+		if (options->getUseRetryAfter())
+		{
+			mProcFlags |= PF_USE_RETRY_AFTER;
+		}
 		mPolicyRetryLimit = options->getRetries();
 		mPolicyRetryLimit = llclamp(mPolicyRetryLimit, HTTP_RETRY_COUNT_MIN, HTTP_RETRY_COUNT_MAX);
 		mTracing = (std::max)(mTracing, llclamp(options->getTrace(), HTTP_TRACE_MIN, HTTP_TRACE_MAX));
@@ -350,6 +378,8 @@ void HttpOpRequest::setupCommon(HttpRequest::policy_t policy_id,
 //
 HttpStatus HttpOpRequest::prepareRequest(HttpService * service)
 {
+	CURLcode code;
+	
 	// Scrub transport and result data for retried op case
 	mCurlActive = false;
 	mCurlHandle = NULL;
@@ -379,64 +409,108 @@ HttpStatus HttpOpRequest::prepareRequest(HttpService * service)
 	// *FIXME:  better error handling later
 	HttpStatus status;
 
-	// Get policy options
+	// Get global policy options
 	HttpPolicyGlobal & policy(service->getPolicy().getGlobalOptions());
 	
 	mCurlHandle = LLCurl::createStandardCurlHandle();
-
-	curl_easy_setopt(mCurlHandle, CURLOPT_WRITEFUNCTION, writeCallback);
-	curl_easy_setopt(mCurlHandle, CURLOPT_READFUNCTION,  readCallback);	
-	curl_easy_setopt(mCurlHandle, CURLOPT_READDATA, this);
-	curl_easy_setopt(mCurlHandle, CURLOPT_WRITEDATA, this);
-	curl_easy_setopt(mCurlHandle, CURLOPT_URL, mReqURL.c_str());
-	curl_easy_setopt(mCurlHandle, CURLOPT_PRIVATE, this);
-	curl_easy_setopt(mCurlHandle, CURLOPT_MAXREDIRS, HTTP_REDIRECTS_DEFAULT);	
-
-	const std::string * opt_value(NULL);
-	long opt_long(0L);
-	policy.get(HttpRequest::GP_LLPROXY, &opt_long);
-	if (opt_long)
+	if (! mCurlHandle)
+	{
+		// We're in trouble.  We'll continue but it won't go well.
+		LL_WARNS("CoreHttp") << "Failed to allocate libcurl easy handle.  Continuing."
+							 << LL_ENDL;
+		return HttpStatus(HttpStatus::LLCORE, HE_BAD_ALLOC);
+	}
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
+	check_curl_easy_code(code, CURLOPT_IPRESOLVE);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_NOSIGNAL, 1);
+	check_curl_easy_code(code, CURLOPT_NOSIGNAL);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_NOPROGRESS, 1);
+	check_curl_easy_code(code, CURLOPT_NOPROGRESS);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_URL, mReqURL.c_str());
+	check_curl_easy_code(code, CURLOPT_URL);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_PRIVATE, this);
+	check_curl_easy_code(code, CURLOPT_PRIVATE);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_ENCODING, "");
+	check_curl_easy_code(code, CURLOPT_ENCODING);
+
+	// The Linksys WRT54G V5 router has an issue with frequent
+	// DNS lookups from LAN machines.  If they happen too often,
+	// like for every HTTP request, the router gets annoyed after
+	// about 700 or so requests and starts issuing TCP RSTs to
+	// new connections.  Reuse the DNS lookups for even a few
+	// seconds and no RSTs.
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_DNS_CACHE_TIMEOUT, 15);
+	check_curl_easy_code(code, CURLOPT_DNS_CACHE_TIMEOUT);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_AUTOREFERER, 1);
+	check_curl_easy_code(code, CURLOPT_AUTOREFERER);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_FOLLOWLOCATION, 1);
+	check_curl_easy_code(code, CURLOPT_FOLLOWLOCATION);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_MAXREDIRS, HTTP_REDIRECTS_DEFAULT);
+	check_curl_easy_code(code, CURLOPT_MAXREDIRS);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_WRITEFUNCTION, writeCallback);
+	check_curl_easy_code(code, CURLOPT_WRITEFUNCTION);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_WRITEDATA, this);
+	check_curl_easy_code(code, CURLOPT_WRITEDATA);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_READFUNCTION, readCallback);
+	check_curl_easy_code(code, CURLOPT_READFUNCTION);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_READDATA, this);
+	check_curl_easy_code(code, CURLOPT_READDATA);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_SSL_VERIFYPEER, 1);
+	check_curl_easy_code(code, CURLOPT_SSL_VERIFYPEER);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_SSL_VERIFYHOST, 0);
+	check_curl_easy_code(code, CURLOPT_SSL_VERIFYHOST);
+
+	if (policy.mUseLLProxy)
 	{
 		// Use the viewer-based thread-safe API which has a
 		// fast/safe check for proxy enable.  Would like to
 		// encapsulate this someway...
 		LLProxy::getInstance()->applyProxySettings(mCurlHandle);
 	}
-	else if (policy.get(HttpRequest::GP_HTTP_PROXY, &opt_value))
+	else if (policy.mHttpProxy.size())
 	{
 		// *TODO:  This is fine for now but get fuller socks5/
 		// authentication thing going later....
-		curl_easy_setopt(mCurlHandle, CURLOPT_PROXY, opt_value->c_str());
-		curl_easy_setopt(mCurlHandle, CURLOPT_PROXYTYPE, CURLPROXY_HTTP);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_PROXY, policy.mHttpProxy.c_str());
+		check_curl_easy_code(code, CURLOPT_PROXY);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_PROXYTYPE, CURLPROXY_HTTP);
+		check_curl_easy_code(code, CURLOPT_PROXYTYPE);
 	}
-	if (policy.get(HttpRequest::GP_CA_PATH, &opt_value))
+	if (policy.mCAPath.size())
 	{
-		curl_easy_setopt(mCurlHandle, CURLOPT_CAPATH, opt_value->c_str());
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_CAPATH, policy.mCAPath.c_str());
+		check_curl_easy_code(code, CURLOPT_CAPATH);
 	}
-	if (policy.get(HttpRequest::GP_CA_FILE, &opt_value))
+	if (policy.mCAFile.size())
 	{
-		curl_easy_setopt(mCurlHandle, CURLOPT_CAINFO, opt_value->c_str());
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_CAINFO, policy.mCAFile.c_str());
+		check_curl_easy_code(code, CURLOPT_CAINFO);
 	}
 	
 	switch (mReqMethod)
 	{
 	case HOR_GET:
-		curl_easy_setopt(mCurlHandle, CURLOPT_HTTPGET, 1);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_HTTPGET, 1);
+		check_curl_easy_code(code, CURLOPT_HTTPGET);
 		mCurlHeaders = curl_slist_append(mCurlHeaders, "Connection: keep-alive");
 		mCurlHeaders = curl_slist_append(mCurlHeaders, "Keep-alive: 300");
 		break;
 		
 	case HOR_POST:
 		{
-			curl_easy_setopt(mCurlHandle, CURLOPT_POST, 1);
-			curl_easy_setopt(mCurlHandle, CURLOPT_ENCODING, "");
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_POST, 1);
+			check_curl_easy_code(code, CURLOPT_POST);
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_ENCODING, "");
+			check_curl_easy_code(code, CURLOPT_ENCODING);
 			long data_size(0);
 			if (mReqBody)
 			{
 				data_size = mReqBody->size();
 			}
-			curl_easy_setopt(mCurlHandle, CURLOPT_POSTFIELDS, static_cast<void *>(NULL));
-			curl_easy_setopt(mCurlHandle, CURLOPT_POSTFIELDSIZE, data_size);
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_POSTFIELDS, static_cast<void *>(NULL));
+			check_curl_easy_code(code, CURLOPT_POSTFIELDS);
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_POSTFIELDSIZE, data_size);
+			check_curl_easy_code(code, CURLOPT_POSTFIELDSIZE);
 			mCurlHeaders = curl_slist_append(mCurlHeaders, "Expect:");
 			mCurlHeaders = curl_slist_append(mCurlHeaders, "Connection: keep-alive");
 			mCurlHeaders = curl_slist_append(mCurlHeaders, "Keep-alive: 300");
@@ -445,14 +519,17 @@ HttpStatus HttpOpRequest::prepareRequest(HttpService * service)
 		
 	case HOR_PUT:
 		{
-			curl_easy_setopt(mCurlHandle, CURLOPT_UPLOAD, 1);
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_UPLOAD, 1);
+			check_curl_easy_code(code, CURLOPT_UPLOAD);
 			long data_size(0);
 			if (mReqBody)
 			{
 				data_size = mReqBody->size();
 			}
-			curl_easy_setopt(mCurlHandle, CURLOPT_INFILESIZE, data_size);
-			curl_easy_setopt(mCurlHandle, CURLOPT_POSTFIELDS, (void *) NULL);
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_INFILESIZE, data_size);
+			check_curl_easy_code(code, CURLOPT_INFILESIZE);
+			code = curl_easy_setopt(mCurlHandle, CURLOPT_POSTFIELDS, (void *) NULL);
+			check_curl_easy_code(code, CURLOPT_POSTFIELDS);
 			mCurlHeaders = curl_slist_append(mCurlHeaders, "Expect:");
 			// *TODO: Should this be 'Keep-Alive' ?
 			mCurlHeaders = curl_slist_append(mCurlHeaders, "Connection: keep-alive");
@@ -470,9 +547,12 @@ HttpStatus HttpOpRequest::prepareRequest(HttpService * service)
 	// Tracing
 	if (mTracing >= HTTP_TRACE_CURL_HEADERS)
 	{
-		curl_easy_setopt(mCurlHandle, CURLOPT_VERBOSE, 1);
-		curl_easy_setopt(mCurlHandle, CURLOPT_DEBUGDATA, this);
-		curl_easy_setopt(mCurlHandle, CURLOPT_DEBUGFUNCTION, debugCallback);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_VERBOSE, 1);
+		check_curl_easy_code(code, CURLOPT_VERBOSE);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_DEBUGDATA, this);
+		check_curl_easy_code(code, CURLOPT_DEBUGDATA);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_DEBUGFUNCTION, debugCallback);
+		check_curl_easy_code(code, CURLOPT_DEBUGFUNCTION);
 	}
 	
 	// There's a CURLOPT for this now...
@@ -500,13 +580,22 @@ HttpStatus HttpOpRequest::prepareRequest(HttpService * service)
 
 	// Request options
 	long timeout(HTTP_REQUEST_TIMEOUT_DEFAULT);
+	long xfer_timeout(HTTP_REQUEST_XFER_TIMEOUT_DEFAULT);
 	if (mReqOptions)
-	{
+ 	{
 		timeout = mReqOptions->getTimeout();
 		timeout = llclamp(timeout, HTTP_REQUEST_TIMEOUT_MIN, HTTP_REQUEST_TIMEOUT_MAX);
+		xfer_timeout = mReqOptions->getTransferTimeout();
+		xfer_timeout = llclamp(xfer_timeout, HTTP_REQUEST_TIMEOUT_MIN, HTTP_REQUEST_TIMEOUT_MAX);
+	}
+	if (xfer_timeout == 0L)
+	{
+		xfer_timeout = timeout;
 	}
-	curl_easy_setopt(mCurlHandle, CURLOPT_TIMEOUT, timeout);
-	curl_easy_setopt(mCurlHandle, CURLOPT_CONNECTTIMEOUT, timeout);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_TIMEOUT, xfer_timeout);
+	check_curl_easy_code(code, CURLOPT_TIMEOUT);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_CONNECTTIMEOUT, timeout);
+	check_curl_easy_code(code, CURLOPT_CONNECTTIMEOUT);
 
 	// Request headers
 	if (mReqHeaders)
@@ -514,12 +603,15 @@ HttpStatus HttpOpRequest::prepareRequest(HttpService * service)
 		// Caller's headers last to override
 		mCurlHeaders = append_headers_to_slist(mReqHeaders, mCurlHeaders);
 	}
-	curl_easy_setopt(mCurlHandle, CURLOPT_HTTPHEADER, mCurlHeaders);
+	code = curl_easy_setopt(mCurlHandle, CURLOPT_HTTPHEADER, mCurlHeaders);
+	check_curl_easy_code(code, CURLOPT_HTTPHEADER);
 
-	if (mProcFlags & (PF_SCAN_RANGE_HEADER | PF_SAVE_HEADERS))
+	if (mProcFlags & (PF_SCAN_RANGE_HEADER | PF_SAVE_HEADERS | PF_USE_RETRY_AFTER))
 	{
-		curl_easy_setopt(mCurlHandle, CURLOPT_HEADERFUNCTION, headerCallback);
-		curl_easy_setopt(mCurlHandle, CURLOPT_HEADERDATA, this);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_HEADERFUNCTION, headerCallback);
+		check_curl_easy_code(code, CURLOPT_HEADERFUNCTION);
+		code = curl_easy_setopt(mCurlHandle, CURLOPT_HEADERDATA, this);
+		check_curl_easy_code(code, CURLOPT_HEADERDATA);
 	}
 	
 	if (status)
@@ -560,7 +652,7 @@ size_t HttpOpRequest::readCallback(void * data, size_t size, size_t nmemb, void
 		{
 			// Warn but continue if the read position moves beyond end-of-body
 			// for some reason.
-			LL_WARNS("HttpCore") << "Request body position beyond body size.  Truncating request body."
+			LL_WARNS("CoreHttp") << "Request body position beyond body size.  Truncating request body."
 								 << LL_ENDL;
 		}
 		return 0;
@@ -577,10 +669,9 @@ size_t HttpOpRequest::headerCallback(void * data, size_t size, size_t nmemb, voi
 {
 	static const char status_line[] = "HTTP/";
 	static const size_t status_line_len = sizeof(status_line) - 1;
-
-	static const char con_ran_line[] = "content-range:";
-	static const size_t con_ran_line_len = sizeof(con_ran_line) - 1;
-
+	static const char con_ran_line[] = "content-range";
+	static const char con_retry_line[] = "retry-after";
+	
 	HttpOpRequest * op(static_cast<HttpOpRequest *>(userdata));
 
 	const size_t hdr_size(size * nmemb);
@@ -594,6 +685,7 @@ size_t HttpOpRequest::headerCallback(void * data, size_t size, size_t nmemb, voi
 		op->mReplyOffset = 0;
 		op->mReplyLength = 0;
 		op->mReplyFullLength = 0;
+		op->mReplyRetryAfter = 0;
 		op->mStatus = HttpStatus();
 		if (op->mReplyHeaders)
 		{
@@ -612,6 +704,53 @@ size_t HttpOpRequest::headerCallback(void * data, size_t size, size_t nmemb, voi
 			--wanted_hdr_size;
 		}
 	}
+
+	// Copy and normalize header fragments for the following
+	// stages.  Would like to modify the data in-place but that
+	// may not be allowed and we need one byte extra for NUL.
+	// At the end of this we will have:
+	//
+	// If ':' present in header:
+	//   1.  name points to text to left of colon which
+	//       will be ascii lower-cased and left and right
+	//       trimmed of whitespace.
+	//   2.  value points to text to right of colon which
+	//       will be left trimmed of whitespace.
+	// Otherwise:
+	//   1.  name points to header which will be left
+	//       trimmed of whitespace.
+	//   2.  value is NULL
+	// Any non-NULL pointer may point to a zero-length string.
+	//
+	if (wanted_hdr_size >= op->mCurlTempLen)
+	{
+		delete [] op->mCurlTemp;
+		op->mCurlTempLen = 2 * wanted_hdr_size + 1;
+		op->mCurlTemp = new char [op->mCurlTempLen];
+	}
+	memcpy(op->mCurlTemp, hdr_data, wanted_hdr_size);
+	op->mCurlTemp[wanted_hdr_size] = '\0';
+	char * name(op->mCurlTemp);
+	char * value(strchr(name, ':'));
+	if (value)
+	{
+		*value++ = '\0';
+		os_strlower(name);
+		name = os_strtrim(name);
+		value = os_strltrim(value);
+	}
+	else
+	{
+		// Doesn't look well-formed, do minimal normalization on it
+		name = os_strltrim(name);
+	}
+
+	// Normalized, now reject headers with empty names.
+	if (! *name)
+	{
+		// No use continuing
+		return hdr_size;
+	}
 	
 	// Save header if caller wants them in the response
 	if (is_header && op->mProcFlags & PF_SAVE_HEADERS)
@@ -621,43 +760,53 @@ size_t HttpOpRequest::headerCallback(void * data, size_t size, size_t nmemb, voi
 		{
 			op->mReplyHeaders = new HttpHeaders;
 		}
-		op->mReplyHeaders->appendNormal(hdr_data, wanted_hdr_size);
+		op->mReplyHeaders->append(name, value ? value : "");
 	}
 
+	// From this point, header-specific processors are free to
+	// modify the header value.
+	
 	// Detect and parse 'Content-Range' headers
-	if (is_header && op->mProcFlags & PF_SCAN_RANGE_HEADER)
+	if (is_header
+		&& op->mProcFlags & PF_SCAN_RANGE_HEADER
+		&& value && *value
+		&& ! strcmp(name, con_ran_line))
 	{
-		char hdr_buffer[128];			// Enough for a reasonable header
-		size_t frag_size((std::min)(wanted_hdr_size, sizeof(hdr_buffer) - 1));
-		
-		memcpy(hdr_buffer, hdr_data, frag_size);
-		hdr_buffer[frag_size] = '\0';
-		if (frag_size > con_ran_line_len &&
-			! os_strncasecmp(hdr_buffer, con_ran_line, con_ran_line_len))
+		unsigned int first(0), last(0), length(0);
+		int status;
+
+		if (! (status = parse_content_range_header(value, &first, &last, &length)))
 		{
-			unsigned int first(0), last(0), length(0);
-			int status;
+			// Success, record the fragment position
+			op->mReplyOffset = first;
+			op->mReplyLength = last - first + 1;
+			op->mReplyFullLength = length;
+		}
+		else if (-1 == status)
+		{
+			// Response is badly formed and shouldn't be accepted
+			op->mStatus = HttpStatus(HttpStatus::LLCORE, HE_INV_CONTENT_RANGE_HDR);
+		}
+		else
+		{
+			// Ignore the unparsable.
+			LL_INFOS_ONCE("CoreHttp") << "Problem parsing odd Content-Range header:  '"
+									  << std::string(hdr_data, wanted_hdr_size)
+									  << "'.  Ignoring."
+									  << LL_ENDL;
+		}
+	}
 
-			if (! (status = parse_content_range_header(hdr_buffer, &first, &last, &length)))
-			{
-				// Success, record the fragment position
-				op->mReplyOffset = first;
-				op->mReplyLength = last - first + 1;
-				op->mReplyFullLength = length;
-			}
-			else if (-1 == status)
-			{
-				// Response is badly formed and shouldn't be accepted
-				op->mStatus = HttpStatus(HttpStatus::LLCORE, HE_INV_CONTENT_RANGE_HDR);
-			}
-			else
-			{
-				// Ignore the unparsable.
-				LL_INFOS_ONCE("CoreHttp") << "Problem parsing odd Content-Range header:  '"
-										  << std::string(hdr_data, frag_size)
-										  << "'.  Ignoring."
-										  << LL_ENDL;
-			}
+	// Detect and parse 'Retry-After' headers
+	if (is_header
+		&& op->mProcFlags & PF_USE_RETRY_AFTER
+		&& value && *value
+		&& ! strcmp(name, con_retry_line))
+	{
+		int time(0);
+		if (! parse_retry_after_header(value, &time))
+		{
+			op->mReplyRetryAfter = time;
 		}
 	}
 
@@ -772,14 +921,16 @@ int parse_content_range_header(char * buffer,
 							   unsigned int * last,
 							   unsigned int * length)
 {
+	static const char * const hdr_whitespace(" \t");
+
 	char * tok_state(NULL), * tok(NULL);
 	bool match(true);
 			
-	if (! os_strtok_r(buffer, hdr_separator, &tok_state))
+	if (! (tok = os_strtok_r(buffer, hdr_whitespace, &tok_state)))
 		match = false;
-	if (match && (tok = os_strtok_r(NULL, hdr_whitespace, &tok_state)))
-		match = 0 == os_strcasecmp("bytes", tok);
-	if (match && ! (tok = os_strtok_r(NULL, " \t", &tok_state)))
+	else
+		match = (0 == os_strcasecmp("bytes", tok));
+	if (match && ! (tok = os_strtok_r(NULL, hdr_whitespace, &tok_state)))
 		match = false;
 	if (match)
 	{
@@ -818,6 +969,25 @@ int parse_content_range_header(char * buffer,
 }
 
 
+int parse_retry_after_header(char * buffer, int * time)
+{
+	char * endptr(buffer);
+	long lcl_time(strtol(buffer, &endptr, 10));
+	if (*endptr == '\0' && endptr != buffer && lcl_time > 0)
+	{
+		*time = lcl_time;
+		return 0;
+	}
+
+	// Could attempt to parse HTTP time here but we're not really
+	// interested in it.  Scheduling based on wallclock time on
+	// user hardware will lead to tears.
+	
+	// Header is there but badly/unexpectedly formed, try to ignore it.
+	return 1;
+}
+
+
 void escape_libcurl_debug_data(char * buffer, size_t len, bool scrub, std::string & safe_line)
 {
 	std::string out;
@@ -854,15 +1024,6 @@ void escape_libcurl_debug_data(char * buffer, size_t len, bool scrub, std::strin
 }
 
 
-int os_strncasecmp(const char *s1, const char *s2, size_t n)
-{
-#if LL_WINDOWS
-	return _strnicmp(s1, s2, n);
-#else
-	return strncasecmp(s1, s2, n);
-#endif	// LL_WINDOWS
-}
-
 
 int os_strcasecmp(const char *s1, const char *s2)
 {
@@ -884,6 +1045,73 @@ char * os_strtok_r(char *str, const char *delim, char ** savestate)
 }
 
 
-}  // end anonymous namespace
+void os_strlower(char * str)
+{
+	for (char c(0); (c = *str); ++str)
+	{
+		*str = tolower(c);
+	}
+}
 
-		
+
+char * os_strtrim(char * lstr)
+{
+	while (' ' == *lstr || '\t' == *lstr)
+	{
+		++lstr;
+	}
+	if (*lstr)
+	{
+		char * rstr(lstr + strlen(lstr));
+		while (lstr < rstr && *--rstr)
+		{
+			if (' ' == *rstr || '\t' == *rstr)
+			{
+				*rstr = '\0';
+			}
+		}
+		llassert(lstr <= rstr);
+	}
+	return lstr;
+}
+
+
+char * os_strltrim(char * lstr)
+{
+	while (' ' == *lstr || '\t' == *lstr)
+	{
+		++lstr;
+	}
+	return lstr;
+}
+
+
+void check_curl_easy_code(CURLcode code, int curl_setopt_option)
+{
+	if (CURLE_OK != code)
+	{
+		// Comment from old llcurl code which may no longer apply:
+		//
+		// linux appears to throw a curl error once per session for a bad initialization
+		// at a pretty random time (when enabling cookies).
+		LL_WARNS("CoreHttp") << "libcurl error detected:  " << curl_easy_strerror(code)
+							 << ", curl_easy_setopt option:  " << curl_setopt_option
+							 << LL_ENDL;
+	}
+}
+
+
+void check_curl_easy_code(CURLcode code)
+{
+	if (CURLE_OK != code)
+	{
+		// Comment from old llcurl code which may no longer apply:
+		//
+		// linux appears to throw a curl error once per session for a bad initialization
+		// at a pretty random time (when enabling cookies).
+		LL_WARNS("CoreHttp") << "libcurl error detected:  " << curl_easy_strerror(code)
+							 << LL_ENDL;
+	}
+}
+
+}  // end anonymous namespace
diff --git a/indra/llcorehttp/_httpoprequest.h b/indra/llcorehttp/_httpoprequest.h
index 74a349b0bf..2f628b5aba 100755
--- a/indra/llcorehttp/_httpoprequest.h
+++ b/indra/llcorehttp/_httpoprequest.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -157,6 +157,7 @@ protected:
 	unsigned int		mProcFlags;
 	static const unsigned int	PF_SCAN_RANGE_HEADER = 0x00000001U;
 	static const unsigned int	PF_SAVE_HEADERS = 0x00000002U;
+	static const unsigned int	PF_USE_RETRY_AFTER = 0x00000004U;
 
 public:
 	// Request data
@@ -174,6 +175,8 @@ public:
 	HttpService *		mCurlService;
 	curl_slist *		mCurlHeaders;
 	size_t				mCurlBodyPos;
+	char *				mCurlTemp;				// Scratch buffer for header processing
+	size_t				mCurlTempLen;
 	
 	// Result data
 	HttpStatus			mStatus;
@@ -183,9 +186,11 @@ public:
 	size_t				mReplyFullLength;
 	HttpHeaders *		mReplyHeaders;
 	std::string			mReplyConType;
+	int					mReplyRetryAfter;
 
 	// Policy data
 	int					mPolicyRetries;
+	int					mPolicy503Retries;
 	HttpTime			mPolicyRetryAt;
 	int					mPolicyRetryLimit;
 };  // end class HttpOpRequest
diff --git a/indra/llcorehttp/_httpopsetget.cpp b/indra/llcorehttp/_httpopsetget.cpp
index 8198528a9b..a5363f9170 100755
--- a/indra/llcorehttp/_httpopsetget.cpp
+++ b/indra/llcorehttp/_httpopsetget.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -27,6 +27,7 @@
 #include "_httpopsetget.h"
 
 #include "httpcommon.h"
+#include "httprequest.h"
 
 #include "_httpservice.h"
 #include "_httppolicy.h"
@@ -43,10 +44,11 @@ namespace LLCore
 
 HttpOpSetGet::HttpOpSetGet()
 	: HttpOperation(),
-	  mIsGlobal(false),
-	  mDoSet(false),
-	  mSetting(-1),				// Nothing requested
-	  mLongValue(0L)
+	  mReqOption(HttpRequest::PO_CONNECTION_LIMIT),
+	  mReqClass(HttpRequest::INVALID_POLICY_ID),
+	  mReqDoSet(false),
+	  mReqLongValue(0L),
+	  mReplyLongValue(0L)
 {}
 
 
@@ -54,37 +56,84 @@ HttpOpSetGet::~HttpOpSetGet()
 {}
 
 
-void HttpOpSetGet::setupGet(HttpRequest::EGlobalPolicy setting)
+HttpStatus HttpOpSetGet::setupGet(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass)
 {
-	mIsGlobal = true;
-	mSetting = setting;
+	HttpStatus status;
+	
+	mReqOption = opt;
+	mReqClass = pclass;
+	return status;
 }
 
 
-void HttpOpSetGet::setupSet(HttpRequest::EGlobalPolicy setting, const std::string & value)
+HttpStatus HttpOpSetGet::setupSet(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass, long value)
 {
-	mIsGlobal = true;
-	mDoSet = true;
-	mSetting = setting;
-	mStrValue = value;
+	HttpStatus status;
+
+	if (! HttpService::sOptionDesc[opt].mIsLong)
+	{
+		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
+	}
+	if (! HttpService::sOptionDesc[opt].mIsDynamic)
+	{
+		return HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_DYNAMIC);
+	}
+	
+	mReqOption = opt;
+	mReqClass = pclass;
+	mReqDoSet = true;
+	mReqLongValue = value;
+	
+	return status;
 }
 
 
-void HttpOpSetGet::stageFromRequest(HttpService * service)
+HttpStatus HttpOpSetGet::setupSet(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass, const std::string & value)
 {
-	HttpPolicyGlobal & pol_opt(service->getPolicy().getGlobalOptions());
-	HttpRequest::EGlobalPolicy setting(static_cast<HttpRequest::EGlobalPolicy>(mSetting));
+	HttpStatus status;
+
+	if (HttpService::sOptionDesc[opt].mIsLong)
+	{
+		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
+	}
+	if (! HttpService::sOptionDesc[opt].mIsDynamic)
+	{
+		return HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_DYNAMIC);
+	}
+
+	mReqOption = opt;
+	mReqClass = pclass;
+	mReqDoSet = true;
+	mReqStrValue = value;
 	
-	if (mDoSet)
+	return status;
+}
+
+
+void HttpOpSetGet::stageFromRequest(HttpService * service)
+{
+	if (mReqDoSet)
 	{
-		mStatus = pol_opt.set(setting, mStrValue);
+		if (HttpService::sOptionDesc[mReqOption].mIsLong)
+		{
+			mStatus = service->setPolicyOption(mReqOption, mReqClass,
+											   mReqLongValue, &mReplyLongValue);
+		}
+		else
+		{
+			mStatus = service->setPolicyOption(mReqOption, mReqClass,
+											   mReqStrValue, &mReplyStrValue);
+		}
 	}
-	if (mStatus)
+	else
 	{
-		const std::string * value(NULL);
-		if ((mStatus = pol_opt.get(setting, &value)))
+		if (HttpService::sOptionDesc[mReqOption].mIsLong)
+		{
+			mStatus = service->getPolicyOption(mReqOption, mReqClass, &mReplyLongValue);
+		}
+		else
 		{
-			mStrValue = *value;
+			mStatus = service->getPolicyOption(mReqOption, mReqClass, &mReplyStrValue);
 		}
 	}
 	
diff --git a/indra/llcorehttp/_httpopsetget.h b/indra/llcorehttp/_httpopsetget.h
index 6966b9d94e..a1e76dd429 100755
--- a/indra/llcorehttp/_httpopsetget.h
+++ b/indra/llcorehttp/_httpopsetget.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -46,7 +46,10 @@ namespace LLCore
 /// configuration settings.
 ///
 /// *NOTE:  Expect this to change.  Don't really like it yet.
-
+///
+/// *TODO:  Can't return values to caller yet.  Need to do
+/// something better with HttpResponse and visitNotifier().
+///
 class HttpOpSetGet : public HttpOperation
 {
 public:
@@ -61,19 +64,23 @@ private:
 
 public:
 	/// Threading:  called by application thread
-	void setupGet(HttpRequest::EGlobalPolicy setting);
-	void setupSet(HttpRequest::EGlobalPolicy setting, const std::string & value);
+	HttpStatus setupGet(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass);
+	HttpStatus setupSet(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass, long value);
+	HttpStatus setupSet(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass, const std::string & value);
 
 	virtual void stageFromRequest(HttpService *);
 
 public:
 	// Request data
-	bool				mIsGlobal;
-	bool				mDoSet;
-	int					mSetting;
-	long				mLongValue;
-	std::string			mStrValue;
-
+	HttpRequest::EPolicyOption	mReqOption;
+	HttpRequest::policy_t		mReqClass;
+	bool						mReqDoSet;
+	long						mReqLongValue;
+	std::string					mReqStrValue;
+
+	// Reply Data
+	long						mReplyLongValue;
+	std::string					mReplyStrValue;
 };  // end class HttpOpSetGet
 
 
diff --git a/indra/llcorehttp/_httppolicy.cpp b/indra/llcorehttp/_httppolicy.cpp
index 014bd37e2e..fd5a93e192 100755
--- a/indra/llcorehttp/_httppolicy.cpp
+++ b/indra/llcorehttp/_httppolicy.cpp
@@ -41,57 +41,70 @@ namespace LLCore
 
 
 // Per-policy-class data for a running system.
-// Collection of queues, parameters, history, metrics, etc.
+// Collection of queues, options and other data
 // for a single policy class.
 //
 // Threading:  accessed only by worker thread
-struct HttpPolicy::State
+struct HttpPolicy::ClassState
 {
 public:
-	State()
-		: mConnMax(HTTP_CONNECTION_LIMIT_DEFAULT),
-		  mConnAt(HTTP_CONNECTION_LIMIT_DEFAULT),
-		  mConnMin(1),
-		  mNextSample(0),
-		  mErrorCount(0),
-		  mErrorFactor(0)
+	ClassState()
+		: mThrottleEnd(0),
+		  mThrottleLeft(0L),
+		  mRequestCount(0L)
 		{}
 	
 	HttpReadyQueue		mReadyQueue;
 	HttpRetryQueue		mRetryQueue;
 
 	HttpPolicyClass		mOptions;
-
-	long				mConnMax;
-	long				mConnAt;
-	long				mConnMin;
-
-	HttpTime			mNextSample;
-	unsigned long		mErrorCount;
-	unsigned long		mErrorFactor;
+	HttpTime			mThrottleEnd;
+	long				mThrottleLeft;
+	long				mRequestCount;
 };
 
 
 HttpPolicy::HttpPolicy(HttpService * service)
-	: mActiveClasses(0),
-	  mState(NULL),
-	  mService(service)
-{}
+	: mService(service)
+{
+	// Create default class
+	mClasses.push_back(new ClassState());
+}
 
 
 HttpPolicy::~HttpPolicy()
 {
 	shutdown();
+
+	for (class_list_t::iterator it(mClasses.begin()); it != mClasses.end(); ++it)
+	{
+		delete (*it);
+	}
+	mClasses.clear();
 	
 	mService = NULL;
 }
 
 
+HttpRequest::policy_t HttpPolicy::createPolicyClass()
+{
+	const HttpRequest::policy_t policy_class(mClasses.size());
+	if (policy_class >= HTTP_POLICY_CLASS_LIMIT)
+	{
+		return HttpRequest::INVALID_POLICY_ID;
+	}
+	mClasses.push_back(new ClassState());
+	return policy_class;
+}
+
+
 void HttpPolicy::shutdown()
 {
-	for (int policy_class(0); policy_class < mActiveClasses; ++policy_class)
+	for (int policy_class(0); policy_class < mClasses.size(); ++policy_class)
 	{
-		HttpRetryQueue & retryq(mState[policy_class].mRetryQueue);
+		ClassState & state(*mClasses[policy_class]);
+		
+		HttpRetryQueue & retryq(state.mRetryQueue);
 		while (! retryq.empty())
 		{
 			HttpOpRequest * op(retryq.top());
@@ -101,7 +114,7 @@ void HttpPolicy::shutdown()
 			op->release();
 		}
 
-		HttpReadyQueue & readyq(mState[policy_class].mReadyQueue);
+		HttpReadyQueue & readyq(state.mReadyQueue);
 		while (! readyq.empty())
 		{
 			HttpOpRequest * op(readyq.top());
@@ -111,28 +124,11 @@ void HttpPolicy::shutdown()
 			op->release();
 		}
 	}
-	delete [] mState;
-	mState = NULL;
-	mActiveClasses = 0;
 }
 
 
-void HttpPolicy::start(const HttpPolicyGlobal & global,
-					   const std::vector<HttpPolicyClass> & classes)
-{
-	llassert_always(! mState);
-
-	mGlobalOptions = global;
-	mActiveClasses = classes.size();
-	mState = new State [mActiveClasses];
-	for (int i(0); i < mActiveClasses; ++i)
-	{
-		mState[i].mOptions = classes[i];
-		mState[i].mConnMax = classes[i].mConnectionLimit;
-		mState[i].mConnAt = mState[i].mConnMax;
-		mState[i].mConnMin = 2;
-	}
-}
+void HttpPolicy::start()
+{}
 
 
 void HttpPolicy::addOp(HttpOpRequest * op)
@@ -140,7 +136,8 @@ void HttpPolicy::addOp(HttpOpRequest * op)
 	const int policy_class(op->mReqPolicy);
 	
 	op->mPolicyRetries = 0;
-	mState[policy_class].mReadyQueue.push(op);
+	op->mPolicy503Retries = 0;
+	mClasses[policy_class]->mReadyQueue.push(op);
 }
 
 
@@ -155,25 +152,39 @@ void HttpPolicy::retryOp(HttpOpRequest * op)
 			5000000				// ... to every 5.0 S.
 		};
 	static const int delta_max(int(LL_ARRAY_SIZE(retry_deltas)) - 1);
-	
+	static const HttpStatus error_503(503);
+
 	const HttpTime now(totalTime());
 	const int policy_class(op->mReqPolicy);
-	
-	const HttpTime delta(retry_deltas[llclamp(op->mPolicyRetries, 0, delta_max)]);
+	HttpTime delta(retry_deltas[llclamp(op->mPolicyRetries, 0, delta_max)]);
+	bool external_delta(false);
+
+	if (op->mReplyRetryAfter > 0 && op->mReplyRetryAfter < 30)
+	{
+		delta = op->mReplyRetryAfter * U64L(1000000);
+		external_delta = true;
+	}
 	op->mPolicyRetryAt = now + delta;
 	++op->mPolicyRetries;
-	LL_WARNS("CoreHttp") << "HTTP request " << static_cast<HttpHandle>(op)
-						 << " retry " << op->mPolicyRetries
-						 << " scheduled for +" << (delta / HttpTime(1000))
-						 << " mS.  Status:  " << op->mStatus.toHex()
-						 << LL_ENDL;
-	if (op->mTracing > 0)
+	if (error_503 == op->mStatus)
+	{
+		++op->mPolicy503Retries;
+	}
+	LL_DEBUGS("CoreHttp") << "HTTP request " << static_cast<HttpHandle>(op)
+						  << " retry " << op->mPolicyRetries
+						  << " scheduled in " << (delta / HttpTime(1000))
+						  << " mS (" << (external_delta ? "external" : "internal")
+						  << ").  Status:  " << op->mStatus.toTerseString()
+						  << LL_ENDL;
+	if (op->mTracing > HTTP_TRACE_OFF)
 	{
 		LL_INFOS("CoreHttp") << "TRACE, ToRetryQueue, Handle:  "
 							 << static_cast<HttpHandle>(op)
+							 << ", Delta:  " << (delta / HttpTime(1000))
+							 << ", Retries:  " << op->mPolicyRetries
 							 << LL_ENDL;
 	}
-	mState[policy_class].mRetryQueue.push(op);
+	mClasses[policy_class]->mRetryQueue.push(op);
 }
 
 
@@ -188,21 +199,43 @@ void HttpPolicy::retryOp(HttpOpRequest * op)
 // the worker thread may sleep hard otherwise will ask for
 // normal polling frequency.
 //
+// Implements a client-side request rate throttle as well.
+// This is intended to mimic and predict throttling behavior
+// of grid services but that is difficult to do with different
+// time bases.  This also represents a rigid coupling between
+// viewer and server that makes it hard to change parameters
+// and I hope we can make this go away with pipelining.
+//
 HttpService::ELoopSpeed HttpPolicy::processReadyQueue()
 {
 	const HttpTime now(totalTime());
 	HttpService::ELoopSpeed result(HttpService::REQUEST_SLEEP);
 	HttpLibcurl & transport(mService->getTransport());
 	
-	for (int policy_class(0); policy_class < mActiveClasses; ++policy_class)
+	for (int policy_class(0); policy_class < mClasses.size(); ++policy_class)
 	{
-		State & state(mState[policy_class]);
-		int active(transport.getActiveCountInClass(policy_class));
-		int needed(state.mConnAt - active);		// Expect negatives here
-
+		ClassState & state(*mClasses[policy_class]);
 		HttpRetryQueue & retryq(state.mRetryQueue);
 		HttpReadyQueue & readyq(state.mReadyQueue);
+
+		if (retryq.empty() && readyq.empty())
+		{
+			continue;
+		}
 		
+		const bool throttle_enabled(state.mOptions.mThrottleRate > 0L);
+		const bool throttle_current(throttle_enabled && now < state.mThrottleEnd);
+
+		if (throttle_current && state.mThrottleLeft <= 0)
+		{
+			// Throttled condition, don't serve this class but don't sleep hard.
+			result = HttpService::NORMAL;
+			continue;
+		}
+
+		int active(transport.getActiveCountInClass(policy_class));
+		int needed(state.mOptions.mConnectionLimit - active);		// Expect negatives here
+
 		if (needed > 0)
 		{
 			// First see if we have any retries...
@@ -216,10 +249,27 @@ HttpService::ELoopSpeed HttpPolicy::processReadyQueue()
 				
 				op->stageFromReady(mService);
 				op->release();
-					
+
+				++state.mRequestCount;
 				--needed;
+				if (throttle_enabled)
+				{
+					if (now >= state.mThrottleEnd)
+					{
+						// Throttle expired, move to next window
+						LL_DEBUGS("CoreHttp") << "Throttle expired with " << state.mThrottleLeft
+											  << " requests to go and " << state.mRequestCount
+											  << " requests issued." << LL_ENDL;
+						state.mThrottleLeft = state.mOptions.mThrottleRate;
+						state.mThrottleEnd = now + HttpTime(1000000);
+					}
+					if (--state.mThrottleLeft <= 0)
+					{
+						goto throttle_on;
+					}
+				}
 			}
-		
+			
 			// Now go on to the new requests...
 			while (needed > 0 && ! readyq.empty())
 			{
@@ -229,10 +279,29 @@ HttpService::ELoopSpeed HttpPolicy::processReadyQueue()
 				op->stageFromReady(mService);
 				op->release();
 					
+				++state.mRequestCount;
 				--needed;
+				if (throttle_enabled)
+				{
+					if (now >= state.mThrottleEnd)
+					{
+						// Throttle expired, move to next window
+						LL_DEBUGS("CoreHttp") << "Throttle expired with " << state.mThrottleLeft
+											  << " requests to go and " << state.mRequestCount
+											  << " requests issued." << LL_ENDL;
+						state.mThrottleLeft = state.mOptions.mThrottleRate;
+						state.mThrottleEnd = now + HttpTime(1000000);
+					}
+					if (--state.mThrottleLeft <= 0)
+					{
+						goto throttle_on;
+					}
+				}
 			}
 		}
-				
+
+	throttle_on:
+		
 		if (! readyq.empty() || ! retryq.empty())
 		{
 			// If anything is ready, continue looping...
@@ -246,9 +315,9 @@ HttpService::ELoopSpeed HttpPolicy::processReadyQueue()
 
 bool HttpPolicy::changePriority(HttpHandle handle, HttpRequest::priority_t priority)
 {
-	for (int policy_class(0); policy_class < mActiveClasses; ++policy_class)
+	for (int policy_class(0); policy_class < mClasses.size(); ++policy_class)
 	{
-		State & state(mState[policy_class]);
+		ClassState & state(*mClasses[policy_class]);
 		// We don't scan retry queue because a priority change there
 		// is meaningless.  The request will be issued based on retry
 		// intervals not priority value, which is now moot.
@@ -276,9 +345,9 @@ bool HttpPolicy::changePriority(HttpHandle handle, HttpRequest::priority_t prior
 
 bool HttpPolicy::cancel(HttpHandle handle)
 {
-	for (int policy_class(0); policy_class < mActiveClasses; ++policy_class)
+	for (int policy_class(0); policy_class < mClasses.size(); ++policy_class)
 	{
-		State & state(mState[policy_class]);
+		ClassState & state(*mClasses[policy_class]);
 
 		// Scan retry queue
 		HttpRetryQueue::container_type & c1(state.mRetryQueue.get_container());
@@ -337,14 +406,14 @@ bool HttpPolicy::stageAfterCompletion(HttpOpRequest * op)
 		LL_WARNS("CoreHttp") << "HTTP request " << static_cast<HttpHandle>(op)
 							 << " failed after " << op->mPolicyRetries
 							 << " retries.  Reason:  " << op->mStatus.toString()
-							 << " (" << op->mStatus.toHex() << ")"
+							 << " (" << op->mStatus.toTerseString() << ")"
 							 << LL_ENDL;
 	}
 	else if (op->mPolicyRetries)
 	{
-		LL_WARNS("CoreHttp") << "HTTP request " << static_cast<HttpHandle>(op)
-							 << " succeeded on retry " << op->mPolicyRetries << "."
-							 << LL_ENDL;
+		LL_DEBUGS("CoreHttp") << "HTTP request " << static_cast<HttpHandle>(op)
+							  << " succeeded on retry " << op->mPolicyRetries << "."
+							  << LL_ENDL;
 	}
 
 	op->stageFromActive(mService);
@@ -352,13 +421,21 @@ bool HttpPolicy::stageAfterCompletion(HttpOpRequest * op)
 	return false;						// not active
 }
 
+	
+HttpPolicyClass & HttpPolicy::getClassOptions(HttpRequest::policy_t pclass)
+{
+	llassert_always(pclass >= 0 && pclass < mClasses.size());
+	
+	return mClasses[pclass]->mOptions;
+}
+
 
 int HttpPolicy::getReadyCount(HttpRequest::policy_t policy_class) const
 {
-	if (policy_class < mActiveClasses)
+	if (policy_class < mClasses.size())
 	{
-		return (mState[policy_class].mReadyQueue.size()
-				+ mState[policy_class].mRetryQueue.size());
+		return (mClasses[policy_class]->mReadyQueue.size()
+				+ mClasses[policy_class]->mRetryQueue.size());
 	}
 	return 0;
 }
diff --git a/indra/llcorehttp/_httppolicy.h b/indra/llcorehttp/_httppolicy.h
index 03d92c0b8e..bf1aa74267 100755
--- a/indra/llcorehttp/_httppolicy.h
+++ b/indra/llcorehttp/_httppolicy.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -60,6 +60,9 @@ private:
 	void operator=(const HttpPolicy &);			// Not defined
 
 public:
+	/// Threading:  called by init thread.
+	HttpRequest::policy_t createPolicyClass();
+	
 	/// Cancel all ready and retry requests sending them to
 	/// their notification queues.  Release state resources
 	/// making further request handling impossible.
@@ -71,9 +74,8 @@ public:
 	/// requests.  One-time call invoked before starting
 	/// the worker thread.
 	///
-	/// Threading:  called by application thread
-	void start(const HttpPolicyGlobal & global,
-			   const std::vector<HttpPolicyClass> & classes);
+	/// Threading:  called by init thread
+	void start();
 
 	/// Give the policy layer some cycles to scan the ready
 	/// queue promoting higher-priority requests to active
@@ -93,7 +95,7 @@ public:
 	/// and should not be modified by anyone until retrieved
 	/// from queue.
 	///
-	/// Threading:  called by any thread
+	/// Threading:  called by worker thread
 	void addOp(HttpOpRequest *);
 
 	/// Similar to addOp, used when a caller wants to retry a
@@ -130,30 +132,39 @@ public:
 	/// Threading:  called by worker thread
 	bool stageAfterCompletion(HttpOpRequest * op);
 	
-	// Get pointer to global policy options.  Caller is expected
-	// to do context checks like no setting once running.
+	/// Get a reference to global policy options.  Caller is expected
+	/// to do context checks like no setting once running.  These
+	/// are done, for example, in @see HttpService interfaces.
 	///
 	/// Threading:  called by any thread *but* the object may
 	/// only be modified by the worker thread once running.
-	///
 	HttpPolicyGlobal & getGlobalOptions()
 		{
 			return mGlobalOptions;
 		}
 
+	/// Get a reference to class policy options.  Caller is expected
+	/// to do context checks like no setting once running.  These
+	/// are done, for example, in @see HttpService interfaces.
+	///
+	/// Threading:  called by any thread *but* the object may
+	/// only be modified by the worker thread once running and
+	/// read accesses by other threads are exposed to races at
+	/// that point.
+	HttpPolicyClass & getClassOptions(HttpRequest::policy_t pclass);
+	
 	/// Get ready counts for a particular policy class
 	///
 	/// Threading:  called by worker thread
 	int getReadyCount(HttpRequest::policy_t policy_class) const;
 	
 protected:
-	struct State;
-
-	int									mActiveClasses;
-	State *								mState;
-	HttpService *						mService;				// Naked pointer, not refcounted, not owner
-	HttpPolicyGlobal					mGlobalOptions;
+	struct ClassState;
+	typedef std::vector<ClassState *>	class_list_t;
 	
+	HttpPolicyGlobal					mGlobalOptions;
+	class_list_t						mClasses;
+	HttpService *						mService;				// Naked pointer, not refcounted, not owner
 };  // end class HttpPolicy
 
 }  // end namespace LLCore
diff --git a/indra/llcorehttp/_httppolicyclass.cpp b/indra/llcorehttp/_httppolicyclass.cpp
index a23b81322c..f34a8e9f1e 100755
--- a/indra/llcorehttp/_httppolicyclass.cpp
+++ b/indra/llcorehttp/_httppolicyclass.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -34,10 +34,10 @@ namespace LLCore
 
 
 HttpPolicyClass::HttpPolicyClass()
-	: mSetMask(0UL),
-	  mConnectionLimit(HTTP_CONNECTION_LIMIT_DEFAULT),
+	: mConnectionLimit(HTTP_CONNECTION_LIMIT_DEFAULT),
 	  mPerHostConnectionLimit(HTTP_CONNECTION_LIMIT_DEFAULT),
-	  mPipelining(0)
+	  mPipelining(HTTP_PIPELINING_DEFAULT),
+	  mThrottleRate(HTTP_THROTTLE_RATE_DEFAULT)
 {}
 
 
@@ -49,75 +49,75 @@ HttpPolicyClass & HttpPolicyClass::operator=(const HttpPolicyClass & other)
 {
 	if (this != &other)
 	{
-		mSetMask = other.mSetMask;
 		mConnectionLimit = other.mConnectionLimit;
 		mPerHostConnectionLimit = other.mPerHostConnectionLimit;
 		mPipelining = other.mPipelining;
+		mThrottleRate = other.mThrottleRate;
 	}
 	return *this;
 }
 
 
 HttpPolicyClass::HttpPolicyClass(const HttpPolicyClass & other)
-	: mSetMask(other.mSetMask),
-	  mConnectionLimit(other.mConnectionLimit),
+	: mConnectionLimit(other.mConnectionLimit),
 	  mPerHostConnectionLimit(other.mPerHostConnectionLimit),
-	  mPipelining(other.mPipelining)
+	  mPipelining(other.mPipelining),
+	  mThrottleRate(other.mThrottleRate)
 {}
 
 
-HttpStatus HttpPolicyClass::set(HttpRequest::EClassPolicy opt, long value)
+HttpStatus HttpPolicyClass::set(HttpRequest::EPolicyOption opt, long value)
 {
 	switch (opt)
 	{
-	case HttpRequest::CP_CONNECTION_LIMIT:
+	case HttpRequest::PO_CONNECTION_LIMIT:
 		mConnectionLimit = llclamp(value, long(HTTP_CONNECTION_LIMIT_MIN), long(HTTP_CONNECTION_LIMIT_MAX));
 		break;
 
-	case HttpRequest::CP_PER_HOST_CONNECTION_LIMIT:
+	case HttpRequest::PO_PER_HOST_CONNECTION_LIMIT:
 		mPerHostConnectionLimit = llclamp(value, long(HTTP_CONNECTION_LIMIT_MIN), mConnectionLimit);
 		break;
 
-	case HttpRequest::CP_ENABLE_PIPELINING:
+	case HttpRequest::PO_ENABLE_PIPELINING:
 		mPipelining = llclamp(value, 0L, 1L);
 		break;
 
+	case HttpRequest::PO_THROTTLE_RATE:
+		mThrottleRate = llclamp(value, 0L, 1000000L);
+		break;
+
 	default:
 		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
 	}
 
-	mSetMask |= 1UL << int(opt);
 	return HttpStatus();
 }
 
 
-HttpStatus HttpPolicyClass::get(HttpRequest::EClassPolicy opt, long * value)
+HttpStatus HttpPolicyClass::get(HttpRequest::EPolicyOption opt, long * value) const
 {
-	static const HttpStatus not_set(HttpStatus::LLCORE, HE_OPT_NOT_SET);
-	long * src(NULL);
-	
 	switch (opt)
 	{
-	case HttpRequest::CP_CONNECTION_LIMIT:
-		src = &mConnectionLimit;
+	case HttpRequest::PO_CONNECTION_LIMIT:
+		*value = mConnectionLimit;
 		break;
 
-	case HttpRequest::CP_PER_HOST_CONNECTION_LIMIT:
-		src = &mPerHostConnectionLimit;
+	case HttpRequest::PO_PER_HOST_CONNECTION_LIMIT:
+		*value = mPerHostConnectionLimit;
 		break;
 
-	case HttpRequest::CP_ENABLE_PIPELINING:
-		src = &mPipelining;
+	case HttpRequest::PO_ENABLE_PIPELINING:
+		*value = mPipelining;
+		break;
+
+	case HttpRequest::PO_THROTTLE_RATE:
+		*value = mThrottleRate;
 		break;
 
 	default:
 		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
 	}
 
-	if (! (mSetMask & (1UL << int(opt))))
-		return not_set;
-
-	*value = *src;
 	return HttpStatus();
 }
 
diff --git a/indra/llcorehttp/_httppolicyclass.h b/indra/llcorehttp/_httppolicyclass.h
index d175413cbd..38f1194ded 100755
--- a/indra/llcorehttp/_httppolicyclass.h
+++ b/indra/llcorehttp/_httppolicyclass.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -34,6 +34,18 @@
 namespace LLCore
 {
 
+/// Options struct for per-class policy options.
+///
+/// Combines both raw blob data access with semantics-enforcing
+/// set/get interfaces.  For internal operations by the worker
+/// thread, just grab the setting directly from instance and test/use
+/// as needed.  When attached to external APIs (the public API
+/// options interfaces) the set/get methods are available to
+/// enforce correct ranges, data types, contexts, etc. and suitable
+/// status values are returned.
+///
+/// Threading:  Single-threaded.  In practice, init thread before
+/// worker starts, worker thread after.
 class HttpPolicyClass
 {
 public:
@@ -44,14 +56,14 @@ public:
 	HttpPolicyClass(const HttpPolicyClass &);			// Not defined
 
 public:
-	HttpStatus set(HttpRequest::EClassPolicy opt, long value);
-	HttpStatus get(HttpRequest::EClassPolicy opt, long * value);
+	HttpStatus set(HttpRequest::EPolicyOption opt, long value);
+	HttpStatus get(HttpRequest::EPolicyOption opt, long * value) const;
 	
 public:
-	unsigned long				mSetMask;
 	long						mConnectionLimit;
 	long						mPerHostConnectionLimit;
 	long						mPipelining;
+	long						mThrottleRate;
 };  // end class HttpPolicyClass
 
 }  // end namespace LLCore
diff --git a/indra/llcorehttp/_httppolicyglobal.cpp b/indra/llcorehttp/_httppolicyglobal.cpp
index 72f409d3b1..1dc95f3dce 100755
--- a/indra/llcorehttp/_httppolicyglobal.cpp
+++ b/indra/llcorehttp/_httppolicyglobal.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -34,8 +34,7 @@ namespace LLCore
 
 
 HttpPolicyGlobal::HttpPolicyGlobal()
-	: mSetMask(0UL),
-	  mConnectionLimit(HTTP_CONNECTION_LIMIT_DEFAULT),
+	: mConnectionLimit(HTTP_CONNECTION_LIMIT_DEFAULT),
 	  mTrace(HTTP_TRACE_OFF),
 	  mUseLLProxy(0)
 {}
@@ -49,7 +48,6 @@ HttpPolicyGlobal & HttpPolicyGlobal::operator=(const HttpPolicyGlobal & other)
 {
 	if (this != &other)
 	{
-		mSetMask = other.mSetMask;
 		mConnectionLimit = other.mConnectionLimit;
 		mCAPath = other.mCAPath;
 		mCAFile = other.mCAFile;
@@ -61,19 +59,19 @@ HttpPolicyGlobal & HttpPolicyGlobal::operator=(const HttpPolicyGlobal & other)
 }
 
 
-HttpStatus HttpPolicyGlobal::set(HttpRequest::EGlobalPolicy opt, long value)
+HttpStatus HttpPolicyGlobal::set(HttpRequest::EPolicyOption opt, long value)
 {
 	switch (opt)
 	{
-	case HttpRequest::GP_CONNECTION_LIMIT:
+	case HttpRequest::PO_CONNECTION_LIMIT:
 		mConnectionLimit = llclamp(value, long(HTTP_CONNECTION_LIMIT_MIN), long(HTTP_CONNECTION_LIMIT_MAX));
 		break;
 
-	case HttpRequest::GP_TRACE:
+	case HttpRequest::PO_TRACE:
 		mTrace = llclamp(value, long(HTTP_TRACE_MIN), long(HTTP_TRACE_MAX));
 		break;
 
-	case HttpRequest::GP_LLPROXY:
+	case HttpRequest::PO_LLPROXY:
 		mUseLLProxy = llclamp(value, 0L, 1L);
 		break;
 
@@ -81,24 +79,23 @@ HttpStatus HttpPolicyGlobal::set(HttpRequest::EGlobalPolicy opt, long value)
 		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
 	}
 
-	mSetMask |= 1UL << int(opt);
 	return HttpStatus();
 }
 
 
-HttpStatus HttpPolicyGlobal::set(HttpRequest::EGlobalPolicy opt, const std::string & value)
+HttpStatus HttpPolicyGlobal::set(HttpRequest::EPolicyOption opt, const std::string & value)
 {
 	switch (opt)
 	{
-	case HttpRequest::GP_CA_PATH:
+	case HttpRequest::PO_CA_PATH:
 		mCAPath = value;
 		break;
 
-	case HttpRequest::GP_CA_FILE:
+	case HttpRequest::PO_CA_FILE:
 		mCAFile = value;
 		break;
 
-	case HttpRequest::GP_HTTP_PROXY:
+	case HttpRequest::PO_HTTP_PROXY:
 		mCAFile = value;
 		break;
 
@@ -106,69 +103,54 @@ HttpStatus HttpPolicyGlobal::set(HttpRequest::EGlobalPolicy opt, const std::stri
 		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
 	}
 	
-	mSetMask |= 1UL << int(opt);
 	return HttpStatus();
 }
 
 
-HttpStatus HttpPolicyGlobal::get(HttpRequest::EGlobalPolicy opt, long * value)
+HttpStatus HttpPolicyGlobal::get(HttpRequest::EPolicyOption opt, long * value) const
 {
-	static const HttpStatus not_set(HttpStatus::LLCORE, HE_OPT_NOT_SET);
-	long * src(NULL);
-	
 	switch (opt)
 	{
-	case HttpRequest::GP_CONNECTION_LIMIT:
-		src = &mConnectionLimit;
+	case HttpRequest::PO_CONNECTION_LIMIT:
+		*value = mConnectionLimit;
 		break;
 
-	case HttpRequest::GP_TRACE:
-		src = &mTrace;
+	case HttpRequest::PO_TRACE:
+		*value = mTrace;
 		break;
 
-	case HttpRequest::GP_LLPROXY:
-		src = &mUseLLProxy;
+	case HttpRequest::PO_LLPROXY:
+		*value = mUseLLProxy;
 		break;
 
 	default:
 		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
 	}
 
-	if (! (mSetMask & (1UL << int(opt))))
-		return not_set;
-
-	*value = *src;
 	return HttpStatus();
 }
 
 
-HttpStatus HttpPolicyGlobal::get(HttpRequest::EGlobalPolicy opt, const std::string ** value)
+HttpStatus HttpPolicyGlobal::get(HttpRequest::EPolicyOption opt, std::string * value) const
 {
-	static const HttpStatus not_set(HttpStatus::LLCORE, HE_OPT_NOT_SET);
-	const std::string * src(NULL);
-
 	switch (opt)
 	{
-	case HttpRequest::GP_CA_PATH:
-		src = &mCAPath;
+	case HttpRequest::PO_CA_PATH:
+		*value = mCAPath;
 		break;
 
-	case HttpRequest::GP_CA_FILE:
-		src = &mCAFile;
+	case HttpRequest::PO_CA_FILE:
+		*value = mCAFile;
 		break;
 
-	case HttpRequest::GP_HTTP_PROXY:
-		src = &mHttpProxy;
+	case HttpRequest::PO_HTTP_PROXY:
+		*value = mHttpProxy;
 		break;
 
 	default:
 		return HttpStatus(HttpStatus::LLCORE, HE_INVALID_ARG);
 	}
 	
-	if (! (mSetMask & (1UL << int(opt))))
-		return not_set;
-
-	*value = src;
 	return HttpStatus();
 }
 
diff --git a/indra/llcorehttp/_httppolicyglobal.h b/indra/llcorehttp/_httppolicyglobal.h
index a50d0e4188..67c4ba9481 100755
--- a/indra/llcorehttp/_httppolicyglobal.h
+++ b/indra/llcorehttp/_httppolicyglobal.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -34,6 +34,18 @@
 namespace LLCore
 {
 
+/// Options struct for global policy options.
+///
+/// Combines both raw blob data access with semantics-enforcing
+/// set/get interfaces.  For internal operations by the worker
+/// thread, just grab the setting directly from instance and test/use
+/// as needed.  When attached to external APIs (the public API
+/// options interfaces) the set/get methods are available to
+/// enforce correct ranges, data types, contexts, etc. and suitable
+/// status values are returned.
+///
+/// Threading:  Single-threaded.  In practice, init thread before
+/// worker starts, worker thread after.
 class HttpPolicyGlobal
 {
 public:
@@ -46,13 +58,12 @@ private:
 	HttpPolicyGlobal(const HttpPolicyGlobal &);			// Not defined
 
 public:
-	HttpStatus set(HttpRequest::EGlobalPolicy opt, long value);
-	HttpStatus set(HttpRequest::EGlobalPolicy opt, const std::string & value);
-	HttpStatus get(HttpRequest::EGlobalPolicy opt, long * value);
-	HttpStatus get(HttpRequest::EGlobalPolicy opt, const std::string ** value);
+	HttpStatus set(HttpRequest::EPolicyOption opt, long value);
+	HttpStatus set(HttpRequest::EPolicyOption opt, const std::string & value);
+	HttpStatus get(HttpRequest::EPolicyOption opt, long * value) const;
+	HttpStatus get(HttpRequest::EPolicyOption opt, std::string * value) const;
 	
 public:
-	unsigned long		mSetMask;
 	long				mConnectionLimit;
 	std::string			mCAPath;
 	std::string			mCAFile;
diff --git a/indra/llcorehttp/_httpservice.cpp b/indra/llcorehttp/_httpservice.cpp
index 0825888d0f..c94249dc2d 100755
--- a/indra/llcorehttp/_httpservice.cpp
+++ b/indra/llcorehttp/_httpservice.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -43,6 +43,18 @@
 namespace LLCore
 {
 
+const HttpService::OptionDescriptor HttpService::sOptionDesc[] =
+{ //    isLong     isDynamic  isGlobal    isClass
+	{	true,		true,		true,		true	},		// PO_CONNECTION_LIMIT
+	{	true,		true,		false,		true	},		// PO_PER_HOST_CONNECTION_LIMIT
+	{	false,		false,		true,		false	},		// PO_CA_PATH
+	{	false,		false,		true,		false	},		// PO_CA_FILE
+	{	false,		true,		true,		false	},		// PO_HTTP_PROXY
+	{	true,		true,		true,		false	},		// PO_LLPROXY
+	{	true,		true,		true,		false	},		// PO_TRACE
+	{	true,		true,		false,		true	},		// PO_ENABLE_PIPELINING
+	{	true,		true,		false,		true	}		// PO_THROTTLE_RATE
+};
 HttpService * HttpService::sInstance(NULL);
 volatile HttpService::EState HttpService::sState(NOT_INITIALIZED);
 
@@ -51,15 +63,9 @@ HttpService::HttpService()
 	  mExitRequested(0U),
 	  mThread(NULL),
 	  mPolicy(NULL),
-	  mTransport(NULL)
-{
-	// Create the default policy class
-	HttpPolicyClass pol_class;
-	pol_class.set(HttpRequest::CP_CONNECTION_LIMIT, HTTP_CONNECTION_LIMIT_DEFAULT);
-	pol_class.set(HttpRequest::CP_PER_HOST_CONNECTION_LIMIT, HTTP_CONNECTION_LIMIT_DEFAULT);
-	pol_class.set(HttpRequest::CP_ENABLE_PIPELINING, 0L);
-	mPolicyClasses.push_back(pol_class);
-}
+	  mTransport(NULL),
+	  mLastPolicy(0)
+{}
 
 
 HttpService::~HttpService()
@@ -149,13 +155,8 @@ void HttpService::term()
 
 HttpRequest::policy_t HttpService::createPolicyClass()
 {
-	const HttpRequest::policy_t policy_class(mPolicyClasses.size());
-	if (policy_class >= HTTP_POLICY_CLASS_LIMIT)
-	{
-		return 0;
-	}
-	mPolicyClasses.push_back(HttpPolicyClass());
-	return policy_class;
+	mLastPolicy = mPolicy->createPolicyClass();
+	return mLastPolicy;
 }
 
 
@@ -188,8 +189,8 @@ void HttpService::startThread()
 	}
 
 	// Push current policy definitions, enable policy & transport components
-	mPolicy->start(mPolicyGlobal, mPolicyClasses);
-	mTransport->start(mPolicyClasses.size());
+	mPolicy->start();
+	mTransport->start(mLastPolicy + 1);
 
 	mThread = new LLCoreInt::HttpThread(boost::bind(&HttpService::threadRun, this, _1));
 	sState = RUNNING;
@@ -322,7 +323,7 @@ HttpService::ELoopSpeed HttpService::processRequestQueue(ELoopSpeed loop)
 		{
 			// Setup for subsequent tracing
 			long tracing(HTTP_TRACE_OFF);
-			mPolicy->getGlobalOptions().get(HttpRequest::GP_TRACE, &tracing);
+			mPolicy->getGlobalOptions().get(HttpRequest::PO_TRACE, &tracing);
 			op->mTracing = (std::max)(op->mTracing, int(tracing));
 
 			if (op->mTracing > HTTP_TRACE_OFF)
@@ -345,4 +346,137 @@ HttpService::ELoopSpeed HttpService::processRequestQueue(ELoopSpeed loop)
 }
 
 
+HttpStatus HttpService::getPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass,
+										long * ret_value)
+{
+	if (opt < HttpRequest::PO_CONNECTION_LIMIT											// option must be in range
+		|| opt >= HttpRequest::PO_LAST													// ditto
+		|| (! sOptionDesc[opt].mIsLong)													// datatype is long
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && pclass > mLastPolicy)			// pclass in valid range
+		|| (pclass == HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsGlobal)	// global setting permitted
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsClass))	// class setting permitted
+																						// can always get, no dynamic check
+	{
+		return HttpStatus(HttpStatus::LLCORE, LLCore::HE_INVALID_ARG);
+	}
+
+	HttpStatus status;
+	if (pclass == HttpRequest::GLOBAL_POLICY_ID)
+	{
+		HttpPolicyGlobal & opts(mPolicy->getGlobalOptions());
+		
+		status = opts.get(opt, ret_value);
+	}
+	else
+	{
+		HttpPolicyClass & opts(mPolicy->getClassOptions(pclass));
+
+		status = opts.get(opt, ret_value);
+	}
+
+	return status;
+}
+
+
+HttpStatus HttpService::getPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass,
+										std::string * ret_value)
+{
+	HttpStatus status(HttpStatus::LLCORE, LLCore::HE_INVALID_ARG);
+
+	if (opt < HttpRequest::PO_CONNECTION_LIMIT											// option must be in range
+		|| opt >= HttpRequest::PO_LAST													// ditto
+		|| (sOptionDesc[opt].mIsLong)													// datatype is string
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && pclass > mLastPolicy)			// pclass in valid range
+		|| (pclass == HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsGlobal)	// global setting permitted
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsClass))	// class setting permitted
+																						// can always get, no dynamic check
+	{
+		return status;
+	}
+
+	// Only global has string values
+	if (pclass == HttpRequest::GLOBAL_POLICY_ID)
+	{
+		HttpPolicyGlobal & opts(mPolicy->getGlobalOptions());
+
+		status = opts.get(opt, ret_value);
+	}
+
+	return status;
+}
+
+
+HttpStatus HttpService::setPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass,
+										long value, long * ret_value)
+{
+	HttpStatus status(HttpStatus::LLCORE, LLCore::HE_INVALID_ARG);
+	
+	if (opt < HttpRequest::PO_CONNECTION_LIMIT											// option must be in range
+		|| opt >= HttpRequest::PO_LAST													// ditto
+		|| (! sOptionDesc[opt].mIsLong)													// datatype is long
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && pclass > mLastPolicy)			// pclass in valid range
+		|| (pclass == HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsGlobal)	// global setting permitted
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsClass)		// class setting permitted
+		|| (RUNNING == sState && ! sOptionDesc[opt].mIsDynamic))						// dynamic setting permitted
+	{
+		return status;
+	}
+
+	if (pclass == HttpRequest::GLOBAL_POLICY_ID)
+	{
+		HttpPolicyGlobal & opts(mPolicy->getGlobalOptions());
+		
+		status = opts.set(opt, value);
+		if (status && ret_value)
+		{
+			status = opts.get(opt, ret_value);
+		}
+	}
+	else
+	{
+		HttpPolicyClass & opts(mPolicy->getClassOptions(pclass));
+
+		status = opts.set(opt, value);
+		if (status && ret_value)
+		{
+			status = opts.get(opt, ret_value);
+		}
+	}
+
+	return status;
+}
+
+
+HttpStatus HttpService::setPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t pclass,
+										const std::string & value, std::string * ret_value)
+{
+	HttpStatus status(HttpStatus::LLCORE, LLCore::HE_INVALID_ARG);
+	
+	if (opt < HttpRequest::PO_CONNECTION_LIMIT											// option must be in range
+		|| opt >= HttpRequest::PO_LAST													// ditto
+		|| (sOptionDesc[opt].mIsLong)													// datatype is string
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && pclass > mLastPolicy)			// pclass in valid range
+		|| (pclass == HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsGlobal)	// global setting permitted
+		|| (pclass != HttpRequest::GLOBAL_POLICY_ID && ! sOptionDesc[opt].mIsClass)		// class setting permitted
+		|| (RUNNING == sState && ! sOptionDesc[opt].mIsDynamic))						// dynamic setting permitted
+	{
+		return status;
+	}
+
+	// Only string values are global at this time
+	if (pclass == HttpRequest::GLOBAL_POLICY_ID)
+	{
+		HttpPolicyGlobal & opts(mPolicy->getGlobalOptions());
+		
+		status = opts.set(opt, value);
+		if (status && ret_value)
+		{
+			status = opts.get(opt, ret_value);
+		}
+	}
+
+	return status;
+}
+	
+
 }  // end namespace LLCore
diff --git a/indra/llcorehttp/_httpservice.h b/indra/llcorehttp/_httpservice.h
index ffe0349d4d..cf23f3ab61 100755
--- a/indra/llcorehttp/_httpservice.h
+++ b/indra/llcorehttp/_httpservice.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -53,6 +53,7 @@ namespace LLCore
 class HttpRequestQueue;
 class HttpPolicy;
 class HttpLibcurl;
+class HttpOpSetGet;
 
 
 /// The HttpService class does the work behind the request queue.  It
@@ -106,7 +107,7 @@ public:
 		NORMAL,					///< continuous polling of request, ready, active queues
 		REQUEST_SLEEP			///< can sleep indefinitely waiting for request queue write
 	};
-		
+
 	static void init(HttpRequestQueue *);
 	static void term();
 
@@ -136,7 +137,7 @@ public:
 	/// acquires its weaknesses.
 	static bool isStopped();
 
-	/// Threading:  callable by consumer thread *once*.
+	/// Threading:  callable by init thread *once*.
 	void startThread();
 
 	/// Threading:  callable by worker thread.
@@ -181,27 +182,38 @@ public:
 		}
 
 	/// Threading:  callable by consumer thread.
-	HttpPolicyGlobal & getGlobalOptions()
-		{
-			return mPolicyGlobal;
-		}
-
-	/// Threading:  callable by consumer thread.
 	HttpRequest::policy_t createPolicyClass();
 	
-	/// Threading:  callable by consumer thread.
-	HttpPolicyClass & getClassOptions(HttpRequest::policy_t policy_class)
-		{
-			llassert(policy_class >= 0 && policy_class < mPolicyClasses.size());
-			return mPolicyClasses[policy_class];
-		}
-	
 protected:
 	void threadRun(LLCoreInt::HttpThread * thread);
 	
 	ELoopSpeed processRequestQueue(ELoopSpeed loop);
+
+protected:
+	friend class HttpOpSetGet;
+	friend class HttpRequest;
+	
+	// Used internally to describe what operations are allowed
+	// on each policy option.
+	struct OptionDescriptor
+	{
+		bool		mIsLong;
+		bool		mIsDynamic;
+		bool		mIsGlobal;
+		bool		mIsClass;
+	};
+		
+	HttpStatus getPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t,
+							   long * ret_value);
+	HttpStatus getPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t,
+							   std::string * ret_value);
+	HttpStatus setPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t,
+							   long value, long * ret_value);
+	HttpStatus setPolicyOption(HttpRequest::EPolicyOption opt, HttpRequest::policy_t,
+							   const std::string & value, std::string * ret_value);
 	
 protected:
+	static const OptionDescriptor		sOptionDesc[HttpRequest::PO_LAST];
 	static HttpService *				sInstance;
 	
 	// === shared data ===
@@ -210,13 +222,13 @@ protected:
 	LLAtomicU32							mExitRequested;
 	LLCoreInt::HttpThread *				mThread;
 	
-	// === consumer-thread-only data ===
-	HttpPolicyGlobal					mPolicyGlobal;
-	std::vector<HttpPolicyClass>		mPolicyClasses;
-	
 	// === working-thread-only data ===
 	HttpPolicy *						mPolicy;		// Simple pointer, has ownership
 	HttpLibcurl *						mTransport;		// Simple pointer, has ownership
+	
+	// === main-thread-only data ===
+	HttpRequest::policy_t				mLastPolicy;
+	
 };  // end class HttpService
 
 }  // end namespace LLCore
diff --git a/indra/llcorehttp/examples/http_texture_load.cpp b/indra/llcorehttp/examples/http_texture_load.cpp
index 909dc5b0cb..73c49687d7 100755
--- a/indra/llcorehttp/examples/http_texture_load.cpp
+++ b/indra/llcorehttp/examples/http_texture_load.cpp
@@ -39,6 +39,7 @@
 #include "httprequest.h"
 #include "httphandler.h"
 #include "httpresponse.h"
+#include "httpoptions.h"
 #include "httpheaders.h"
 #include "bufferarray.h"
 #include "_mutex.h"
@@ -57,6 +58,7 @@ void usage(std::ostream & out);
 
 // Default command line settings
 static int concurrency_limit(40);
+static int highwater(100);
 static char url_format[1024] = "http://example.com/some/path?texture_id=%s.texture";
 
 #if defined(WIN32)
@@ -79,11 +81,11 @@ public:
 	WorkingSet();
 	~WorkingSet();
 
-	bool reload(LLCore::HttpRequest *);
+	bool reload(LLCore::HttpRequest *, LLCore::HttpOptions *);
 	
 	virtual void onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response);
 
-	void loadTextureUuids(FILE * in);
+	void loadAssetUuids(FILE * in);
 	
 public:
 	struct Spec
@@ -93,24 +95,27 @@ public:
 		int				mLength;
 	};
 	typedef std::set<LLCore::HttpHandle> handle_set_t;
-	typedef std::vector<Spec> texture_list_t;
+	typedef std::vector<Spec> asset_list_t;
 	
 public:
 	bool						mVerbose;
 	bool						mRandomRange;
-	int							mMaxConcurrency;
+	int							mRequestLowWater;
+	int							mRequestHighWater;
 	handle_set_t				mHandles;
 	int							mRemaining;
 	int							mLimit;
 	int							mAt;
 	std::string					mUrl;
-	texture_list_t				mTextures;
+	asset_list_t				mAssets;
 	int							mErrorsApi;
 	int							mErrorsHttp;
 	int							mErrorsHttp404;
 	int							mErrorsHttp416;
 	int							mErrorsHttp500;
 	int							mErrorsHttp503;
+	int							mRetries;
+	int							mRetriesHttp503;
 	int							mSuccesses;
 	long						mByteCount;
 	LLCore::HttpHeaders *		mHeaders;
@@ -158,7 +163,7 @@ int main(int argc, char** argv)
 	bool do_verbose(false);
 	
 	int option(-1);
-	while (-1 != (option = getopt(argc, argv, "u:c:h?Rv")))
+	while (-1 != (option = getopt(argc, argv, "u:c:h?RvH:")))
 	{
 		switch (option)
 		{
@@ -182,6 +187,21 @@ int main(int argc, char** argv)
 			}
 			break;
 
+		case 'H':
+		    {
+				unsigned long value;
+				char * end;
+
+				value = strtoul(optarg, &end, 10);
+				if (value < 1 || value > 100 || *end != '\0')
+				{
+					usage(std::cerr);
+					return 1;
+				}
+				highwater = value;
+			}
+			break;
+
 		case 'R':
 			do_random = true;
 			break;
@@ -216,25 +236,32 @@ int main(int argc, char** argv)
 	// Initialization
 	init_curl();
 	LLCore::HttpRequest::createService();
-	LLCore::HttpRequest::setPolicyClassOption(LLCore::HttpRequest::DEFAULT_POLICY_ID,
-											  LLCore::HttpRequest::CP_CONNECTION_LIMIT,
-											  concurrency_limit);
+	LLCore::HttpRequest::setStaticPolicyOption(LLCore::HttpRequest::PO_CONNECTION_LIMIT,
+											   LLCore::HttpRequest::DEFAULT_POLICY_ID,
+											   concurrency_limit,
+											   NULL);
 	LLCore::HttpRequest::startThread();
 	
 	// Get service point
 	LLCore::HttpRequest * hr = new LLCore::HttpRequest();
 
+	// Get request options
+	LLCore::HttpOptions * opt = new LLCore::HttpOptions();
+	opt->setRetries(12);
+	opt->setUseRetryAfter(true);
+	
 	// Get a handler/working set
 	WorkingSet ws;
 
 	// Fill the working set with work
 	ws.mUrl = url_format;
-	ws.loadTextureUuids(uuids);
+	ws.loadAssetUuids(uuids);
 	ws.mRandomRange = do_random;
 	ws.mVerbose = do_verbose;
-	ws.mMaxConcurrency = 100;
+	ws.mRequestHighWater = highwater;
+	ws.mRequestLowWater = ws.mRequestHighWater / 2;
 	
-	if (! ws.mTextures.size())
+	if (! ws.mAssets.size())
 	{
 		std::cerr << "No UUIDs found in file '" << argv[optind] << "'." << std::endl;
 		return 1;
@@ -246,9 +273,9 @@ int main(int argc, char** argv)
 	
 	// Run it
 	int passes(0);
-	while (! ws.reload(hr))
+	while (! ws.reload(hr, opt))
 	{
-		hr->update(5000000);
+		hr->update(0);
 		ms_sleep(2);
 		if (0 == (++passes % 200))
 		{
@@ -265,6 +292,8 @@ int main(int argc, char** argv)
 	std::cout << "HTTP 404 errors: " << ws.mErrorsHttp404 << "  HTTP 416 errors: " << ws.mErrorsHttp416
 			  << "  HTTP 500 errors:  " << ws.mErrorsHttp500 << "  HTTP 503 errors: " << ws.mErrorsHttp503 
 			  << std::endl;
+	std::cout << "Retries: " << ws.mRetries << "  Retries on 503: " << ws.mRetriesHttp503
+			  << std::endl;
 	std::cout << "User CPU: " << (metrics.mEndUTime - metrics.mStartUTime)
 			  << " uS  System CPU: " << (metrics.mEndSTime - metrics.mStartSTime)
 			  << " uS  Wall Time: "  << (metrics.mEndWallTime - metrics.mStartWallTime)
@@ -275,6 +304,8 @@ int main(int argc, char** argv)
 	// Clean up
 	hr->requestStopThread(NULL);
 	ms_sleep(1000);
+	opt->release();
+	opt = NULL;
 	delete hr;
 	LLCore::HttpRequest::destroyService();
 	term_curl();
@@ -300,8 +331,10 @@ void usage(std::ostream & out)
 		" -u <url_format>       printf-style format string for URL generation\n"
 		"                       Default:  " << url_format << "\n"
 		" -R                    Issue GETs with random Range: headers\n"
-		" -c <limit>            Maximum request concurrency.  Range:  [1..100]\n"
+		" -c <limit>            Maximum connection concurrency.  Range:  [1..100]\n"
 		"                       Default:  " << concurrency_limit << "\n"
+		" -H <limit>            HTTP request highwater (requests fed to llcorehttp).\n"
+		"                       Range:  [1..100]  Default:  " << highwater << "\n"
 		" -v                    Verbose mode.  Issue some chatter while running\n"
 		" -h                    print this help\n"
 		"\n"
@@ -322,10 +355,12 @@ WorkingSet::WorkingSet()
 	  mErrorsHttp416(0),
 	  mErrorsHttp500(0),
 	  mErrorsHttp503(0),
+	  mRetries(0),
+	  mRetriesHttp503(0),
 	  mSuccesses(0),
 	  mByteCount(0L)
 {
-	mTextures.reserve(30000);
+	mAssets.reserve(30000);
 
 	mHeaders = new LLCore::HttpHeaders;
 	mHeaders->append("Accept", "image/x-j2c");
@@ -342,29 +377,35 @@ WorkingSet::~WorkingSet()
 }
 
 
-bool WorkingSet::reload(LLCore::HttpRequest * hr)
+bool WorkingSet::reload(LLCore::HttpRequest * hr, LLCore::HttpOptions * opt)
 {
-	int to_do((std::min)(mRemaining, mMaxConcurrency - int(mHandles.size())));
+	if (mRequestLowWater <= mHandles.size())
+	{
+		// Haven't fallen below low-water level yet.
+		return false;
+	}
+	
+	int to_do((std::min)(mRemaining, mRequestHighWater - int(mHandles.size())));
 
 	for (int i(0); i < to_do; ++i)
 	{
 		char buffer[1024];
 #if	defined(WIN32)
-		_snprintf_s(buffer, sizeof(buffer), sizeof(buffer) - 1, mUrl.c_str(), mTextures[mAt].mUuid.c_str());
+		_snprintf_s(buffer, sizeof(buffer), sizeof(buffer) - 1, mUrl.c_str(), mAssets[mAt].mUuid.c_str());
 #else
-		snprintf(buffer, sizeof(buffer), mUrl.c_str(), mTextures[mAt].mUuid.c_str());
+		snprintf(buffer, sizeof(buffer), mUrl.c_str(), mAssets[mAt].mUuid.c_str());
 #endif
-		int offset(mRandomRange ? ((unsigned long) rand()) % 1000000UL : mTextures[mAt].mOffset);
-		int length(mRandomRange ? ((unsigned long) rand()) % 1000000UL : mTextures[mAt].mLength);
+		int offset(mRandomRange ? ((unsigned long) rand()) % 1000000UL : mAssets[mAt].mOffset);
+		int length(mRandomRange ? ((unsigned long) rand()) % 1000000UL : mAssets[mAt].mLength);
 
 		LLCore::HttpHandle handle;
 		if (offset || length)
 		{
-			handle = hr->requestGetByteRange(0, 0, buffer, offset, length, NULL, mHeaders, this);
+			handle = hr->requestGetByteRange(0, 0, buffer, offset, length, opt, mHeaders, this);
 		}
 		else
 		{
-			handle = hr->requestGet(0, 0, buffer, NULL, mHeaders, this);
+			handle = hr->requestGet(0, 0, buffer, opt, mHeaders, this);
 		}
 		if (! handle)
 		{
@@ -410,7 +451,7 @@ void WorkingSet::onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * r
 		{
 			// More success
 			LLCore::BufferArray * data(response->getBody());
-			mByteCount += data->size();
+			mByteCount += data ? data->size() : 0;
 			++mSuccesses;
 		}
 		else
@@ -446,6 +487,10 @@ void WorkingSet::onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * r
 				++mErrorsApi;
 			}
 		}
+		unsigned int retry(0U), retry_503(0U);
+		response->getRetries(&retry, &retry_503);
+		mRetries += int(retry);
+		mRetriesHttp503 += int(retry_503);
 		mHandles.erase(it);
 	}
 
@@ -459,21 +504,21 @@ void WorkingSet::onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * r
 }
 
 
-void WorkingSet::loadTextureUuids(FILE * in)
+void WorkingSet::loadAssetUuids(FILE * in)
 {
 	char buffer[1024];
 
 	while (fgets(buffer, sizeof(buffer), in))
 	{
-		WorkingSet::Spec texture;
+		WorkingSet::Spec asset;
 		char * state(NULL);
 		char * token = strtok_r(buffer, " \t\n,", &state);
 		if (token && 36 == strlen(token))
 		{
 			// Close enough for this function
-			texture.mUuid = token;
-			texture.mOffset = 0;
-			texture.mLength = 0;
+			asset.mUuid = token;
+			asset.mOffset = 0;
+			asset.mLength = 0;
 			token = strtok_r(buffer, " \t\n,", &state);
 			if (token)
 			{
@@ -482,14 +527,14 @@ void WorkingSet::loadTextureUuids(FILE * in)
 				if (token)
 				{
 					int length(atoi(token));
-					texture.mOffset = offset;
-					texture.mLength = length;
+					asset.mOffset = offset;
+					asset.mLength = length;
 				}
 			}
-			mTextures.push_back(texture);
+			mAssets.push_back(asset);
 		}
 	}
-	mRemaining = mLimit = mTextures.size();
+	mRemaining = mLimit = mAssets.size();
 }
 
 
diff --git a/indra/llcorehttp/httpcommon.cpp b/indra/llcorehttp/httpcommon.cpp
index 0738760763..c2f15155ac 100755
--- a/indra/llcorehttp/httpcommon.cpp
+++ b/indra/llcorehttp/httpcommon.cpp
@@ -70,7 +70,8 @@ std::string HttpStatus::toString() const
 			"Invalid datatype for argument or option",
 			"Option has not been explicitly set",
 			"Option is not dynamic and must be set early",
-			"Invalid HTTP status code received from server"
+			"Invalid HTTP status code received from server",
+			"Could not allocate required resource"
 		};
 	static const int llcore_errors_count(sizeof(llcore_errors) / sizeof(llcore_errors[0]));
 
@@ -177,6 +178,44 @@ std::string HttpStatus::toString() const
 }
 
 
+std::string HttpStatus::toTerseString() const
+{
+	std::ostringstream result;
+
+	unsigned int error_value((unsigned short) mStatus);
+	
+	switch (mType)
+	{
+	case EXT_CURL_EASY:
+		result << "Easy_";
+		break;
+		
+	case EXT_CURL_MULTI:
+		result << "Multi_";
+		break;
+		
+	case LLCORE:
+		result << "Core_";
+		break;
+
+	default:
+		if (isHttpStatus())
+		{
+			result << "Http_";
+			error_value = mType;
+		}
+		else
+		{
+			result << "Unknown_";
+		}
+		break;
+	}
+	
+	result << error_value;
+	return result.str();
+}
+
+
 // Pass true on statuses that might actually be cleared by a
 // retry.  Library failures, calling problems, etc. aren't
 // going to be fixed by squirting bits all over the Net.
@@ -206,6 +245,5 @@ bool HttpStatus::isRetryable() const
 			*this == inv_cont_range);	// Short data read disagrees with content-range
 }
 
-		
 } // end namespace LLCore
 
diff --git a/indra/llcorehttp/httpcommon.h b/indra/llcorehttp/httpcommon.h
index 41fb5164cf..9601f94125 100755
--- a/indra/llcorehttp/httpcommon.h
+++ b/indra/llcorehttp/httpcommon.h
@@ -29,9 +29,9 @@
 
 /// @package LLCore::HTTP
 ///
-/// This library implements a high-level, Indra-code-free client interface to
-/// HTTP services based on actual patterns found in the viewer and simulator.
-/// Interfaces are similar to those supplied by the legacy classes
+/// This library implements a high-level, Indra-code-free (somewhat) client
+/// interface to HTTP services based on actual patterns found in the viewer
+/// and simulator.  Interfaces are similar to those supplied by the legacy classes
 /// LLCurlRequest and LLHTTPClient.  To that is added a policy scheme that
 /// allows an application to specify connection behaviors:  limits on
 /// connections, HTTP keepalive, HTTP pipelining, retry-on-error limits, etc.
@@ -52,7 +52,7 @@
 /// - "llcorehttp/httprequest.h"
 /// - "llcorehttp/httpresponse.h"
 ///
-/// The library is still under early development and particular users
+/// The library is still under development and particular users
 /// may need access to internal implementation details that are found
 /// in the _*.h header files.  But this is a crutch to be avoided if at
 /// all possible and probably indicates some interface work is neeeded.
@@ -66,6 +66,8 @@
 ///   .  CRYPTO_set_id_callback(...)
 /// - HttpRequest::createService() called to instantiate singletons
 ///   and support objects.
+/// - HttpRequest::startThread() to kick off the worker thread and
+///   begin servicing requests.
 ///
 /// An HTTP consumer in an application, and an application may have many
 /// consumers, does a few things:
@@ -91,10 +93,12 @@
 ///   objects.
 /// - Do completion processing in your onCompletion() method.
 ///
-/// Code fragments:
-/// Rather than a poorly-maintained example in comments, look in the
-/// example subdirectory which is a minimal yet functional tool to do
-/// GET request performance testing.  With four calls:
+/// Code fragments.
+///
+/// Initialization.  Rather than a poorly-maintained example in
+/// comments, look in the example subdirectory which is a minimal
+/// yet functional tool to do GET request performance testing.
+/// With four calls:
 ///
 ///   	init_curl();
 ///     LLCore::HttpRequest::createService();
@@ -103,7 +107,85 @@
 ///
 /// the program is basically ready to issue requests.
 ///
-
+/// HttpHandler.  Having started life as a non-indra library,
+/// this code broke away from the classic Responder model and
+/// introduced a handler class to represent an interface for
+/// request responses.  This is a non-reference-counted entity
+/// which can be used as a base class or a mixin.  An instance
+/// of a handler can be used for each request or can be shared
+/// among any number of requests.  Your choice but expect to
+/// code something like the following:
+///
+///     class AppHandler : public LLCore::HttpHandler
+///     {
+///     public:
+///         virtual void onCompleted(HttpHandle handle,
+///                                  HttpResponse * response)
+///         {
+///             ...
+///         }
+///         ...
+///     };
+///     ...
+///     handler = new handler(...);
+///
+///
+/// Issuing requests.  Using 'hr' above,
+///
+///     hr->requestGet(HttpRequest::DEFAULT_POLICY_ID,
+///                    0,				// Priority, not used yet
+///                    url,
+///                    NULL,			// options
+///                    NULL,            // additional headers
+///                    handler);
+///
+/// If that returns a value other than LLCORE_HTTP_HANDLE_INVALID,
+/// the request was successfully issued and there will eventally
+/// be a status delivered to the handler.  If invalid is returnedd,
+/// the actual status can be retrieved by calling hr->getStatus().
+///
+/// Completing requests and delivering notifications.  Operations
+/// are all performed by the worker thread and will be driven to
+/// completion regardless of caller actions.  Notification of
+/// completion (success or failure) is done by calls to
+/// HttpRequest::update() which will invoke handlers for completed
+/// requests:
+///
+///     hr->update(0);
+///       // Callbacks into handler->onCompleted()
+///
+///
+/// Threads.
+///
+/// Threads are supported and used by this library.  The various
+/// classes, methods and members are documented with thread
+/// constraints which programmers must follow and which are
+/// defined as follows:
+///
+/// consumer	Any thread that has instanced HttpRequest and is
+///             issuing requests.  A particular instance can only
+///             be used by one consumer thread but a consumer may
+///             have many instances available to it.
+/// init		Special consumer thread, usually the main thread,
+///             involved in setting up the library at startup.
+/// worker      Thread used internally by the library to perform
+///             HTTP operations.  Consumers will not have to deal
+///             with this thread directly but some APIs are reserved
+///             to it.
+/// any         Consumer or worker thread.
+///
+/// For the most part, API users will not have to do much in the
+/// way of ensuring thread safely.  However, there is a tremendous
+/// amount of sharing between threads of read-only data.  So when
+/// documentation declares that an option or header instance
+/// becomes shared between consumer and worker, the consumer must
+/// not modify the shared object.
+///
+/// Internally, there is almost no thread synchronization.  During
+/// normal operations (non-init, non-term), only the request queue
+/// and the multiple reply queues are shared between threads and
+/// only here are mutexes used.
+///
 
 #include "linden_common.h"		// Modifies curl/curl.h interfaces
 
@@ -164,7 +246,10 @@ enum HttpError
 	HE_OPT_NOT_DYNAMIC = 8,
 	
 	// Invalid HTTP status code returned by server
-	HE_INVALID_HTTP_STATUS = 9
+	HE_INVALID_HTTP_STATUS = 9,
+	
+	// Couldn't allocate resource, typically libcurl handle
+	HE_BAD_ALLOC = 10
 	
 }; // end enum HttpError
 
@@ -239,9 +324,10 @@ struct HttpStatus
 			return *this;
 		}
 	
-	static const type_enum_t EXT_CURL_EASY = 0;
-	static const type_enum_t EXT_CURL_MULTI = 1;
-	static const type_enum_t LLCORE = 2;
+	static const type_enum_t EXT_CURL_EASY = 0;			///< mStatus is an error from a curl_easy_*() call
+	static const type_enum_t EXT_CURL_MULTI = 1;		///< mStatus is an error from a curl_multi_*() call
+	static const type_enum_t LLCORE = 2;				///< mStatus is an HE_* error code
+														///< 100-999 directly represent HTTP status codes
 	
 	type_enum_t			mType;
 	short				mStatus;
@@ -297,6 +383,14 @@ struct HttpStatus
 	/// LLCore itself).
 	std::string toString() const;
 
+	/// Convert status to a compact string representation
+	/// of the form:  "<type>_<value>".  The <type> will be
+	/// one of:  Core, Http, Easy, Multi, Unknown.  And
+	/// <value> will be an unsigned integer.  More easily
+	/// interpreted than the hex representation, it's still
+	/// compact and easily searched.
+	std::string toTerseString() const;
+
 	/// Returns true if the status value represents an
 	/// HTTP response status (100 - 999).
 	bool isHttpStatus() const
diff --git a/indra/llcorehttp/httpoptions.cpp b/indra/llcorehttp/httpoptions.cpp
index 1699d19f8d..5bf1ecb4a5 100755
--- a/indra/llcorehttp/httpoptions.cpp
+++ b/indra/llcorehttp/httpoptions.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -38,7 +38,9 @@ HttpOptions::HttpOptions()
 	  mWantHeaders(false),
 	  mTracing(HTTP_TRACE_OFF),
 	  mTimeout(HTTP_REQUEST_TIMEOUT_DEFAULT),
-	  mRetries(HTTP_RETRY_COUNT_DEFAULT)
+	  mTransferTimeout(HTTP_REQUEST_XFER_TIMEOUT_DEFAULT),
+	  mRetries(HTTP_RETRY_COUNT_DEFAULT),
+	  mUseRetryAfter(HTTP_USE_RETRY_AFTER_DEFAULT)
 {}
 
 
@@ -64,10 +66,21 @@ void HttpOptions::setTimeout(unsigned int timeout)
 }
 
 
+void HttpOptions::setTransferTimeout(unsigned int timeout)
+{
+	mTransferTimeout = timeout;
+}
+
+
 void HttpOptions::setRetries(unsigned int retries)
 {
 	mRetries = retries;
 }
 
+void HttpOptions::setUseRetryAfter(bool use_retry)
+{
+	mUseRetryAfter = use_retry;
+}
+
 
 }   // end namespace LLCore
diff --git a/indra/llcorehttp/httpoptions.h b/indra/llcorehttp/httpoptions.h
index 97e46a8cd3..4ab5ff18c4 100755
--- a/indra/llcorehttp/httpoptions.h
+++ b/indra/llcorehttp/httpoptions.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -68,36 +68,55 @@ protected:
 	void operator=(const HttpOptions &);		// Not defined
 
 public:
+	// Default:   false
 	void				setWantHeaders(bool wanted);
 	bool				getWantHeaders() const
 		{
 			return mWantHeaders;
 		}
-	
+
+	// Default:  0
 	void				setTrace(int long);
 	int					getTrace() const
 		{
 			return mTracing;
 		}
 
+	// Default:  30
 	void				setTimeout(unsigned int timeout);
 	unsigned int		getTimeout() const
 		{
 			return mTimeout;
 		}
 
+	// Default:  0
+	void				setTransferTimeout(unsigned int timeout);
+	unsigned int		getTransferTimeout() const
+		{
+			return mTransferTimeout;
+		}
+
+	// Default:  8
 	void				setRetries(unsigned int retries);
 	unsigned int		getRetries() const
 		{
 			return mRetries;
 		}
+
+	// Default:  true
+	void				setUseRetryAfter(bool use_retry);
+	bool				getUseRetryAfter() const
+		{
+			return mUseRetryAfter;
+		}
 	
 protected:
 	bool				mWantHeaders;
 	int					mTracing;
 	unsigned int		mTimeout;
+	unsigned int		mTransferTimeout;
 	unsigned int		mRetries;
-	
+	bool				mUseRetryAfter;
 }; // end class HttpOptions
 
 
diff --git a/indra/llcorehttp/httprequest.cpp b/indra/llcorehttp/httprequest.cpp
index 9b739a8825..7b1888e3eb 100755
--- a/indra/llcorehttp/httprequest.cpp
+++ b/indra/llcorehttp/httprequest.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -54,12 +54,8 @@ namespace LLCore
 // ====================================
 
 
-HttpRequest::policy_t HttpRequest::sNextPolicyID(1);
-
-
 HttpRequest::HttpRequest()
-	: //HttpHandler(),
-	  mReplyQueue(NULL),
+	: mReplyQueue(NULL),
 	  mRequestQueue(NULL)
 {
 	mRequestQueue = HttpRequestQueue::instanceOf();
@@ -90,45 +86,91 @@ HttpRequest::~HttpRequest()
 // ====================================
 
 
-HttpStatus HttpRequest::setPolicyGlobalOption(EGlobalPolicy opt, long value)
+HttpRequest::policy_t HttpRequest::createPolicyClass()
 {
 	if (HttpService::RUNNING == HttpService::instanceOf()->getState())
 	{
-		return HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_DYNAMIC);
+		return 0;
 	}
-	return HttpService::instanceOf()->getGlobalOptions().set(opt, value);
+	return HttpService::instanceOf()->createPolicyClass();
 }
 
 
-HttpStatus HttpRequest::setPolicyGlobalOption(EGlobalPolicy opt, const std::string & value)
+HttpStatus HttpRequest::setStaticPolicyOption(EPolicyOption opt, policy_t pclass,
+											  long value, long * ret_value)
 {
 	if (HttpService::RUNNING == HttpService::instanceOf()->getState())
 	{
 		return HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_DYNAMIC);
 	}
-	return HttpService::instanceOf()->getGlobalOptions().set(opt, value);
+	return HttpService::instanceOf()->setPolicyOption(opt, pclass, value, ret_value);
 }
 
 
-HttpRequest::policy_t HttpRequest::createPolicyClass()
+HttpStatus HttpRequest::setStaticPolicyOption(EPolicyOption opt, policy_t pclass,
+											  const std::string & value, std::string * ret_value)
 {
 	if (HttpService::RUNNING == HttpService::instanceOf()->getState())
 	{
-		return 0;
+		return HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_DYNAMIC);
 	}
-	return HttpService::instanceOf()->createPolicyClass();
+	return HttpService::instanceOf()->setPolicyOption(opt, pclass, value, ret_value);
 }
 
 
-HttpStatus HttpRequest::setPolicyClassOption(policy_t policy_id,
-											 EClassPolicy opt,
-											 long value)
+HttpHandle HttpRequest::setPolicyOption(EPolicyOption opt, policy_t pclass,
+										long value, HttpHandler * handler)
 {
-	if (HttpService::RUNNING == HttpService::instanceOf()->getState())
+	HttpStatus status;
+	HttpHandle handle(LLCORE_HTTP_HANDLE_INVALID);
+
+	HttpOpSetGet * op = new HttpOpSetGet();
+	if (! (status = op->setupSet(opt, pclass, value)))
 	{
-		return HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_DYNAMIC);
+		op->release();
+		mLastReqStatus = status;
+		return handle;
+	}
+	op->setReplyPath(mReplyQueue, handler);
+	if (! (status = mRequestQueue->addOp(op)))			// transfers refcount
+	{
+		op->release();
+		mLastReqStatus = status;
+		return handle;
+	}
+	
+	mLastReqStatus = status;
+	handle = static_cast<HttpHandle>(op);
+	
+	return handle;
+}
+
+
+HttpHandle HttpRequest::setPolicyOption(EPolicyOption opt, policy_t pclass,
+										const std::string & value, HttpHandler * handler)
+{
+	HttpStatus status;
+	HttpHandle handle(LLCORE_HTTP_HANDLE_INVALID);
+
+	HttpOpSetGet * op = new HttpOpSetGet();
+	if (! (status = op->setupSet(opt, pclass, value)))
+	{
+		op->release();
+		mLastReqStatus = status;
+		return handle;
+	}
+	op->setReplyPath(mReplyQueue, handler);
+	if (! (status = mRequestQueue->addOp(op)))			// transfers refcount
+	{
+		op->release();
+		mLastReqStatus = status;
+		return handle;
 	}
-	return HttpService::instanceOf()->getClassOptions(policy_id).set(opt, value);
+	
+	mLastReqStatus = status;
+	handle = static_cast<HttpHandle>(op);
+	
+	return handle;
 }
 
 
@@ -474,31 +516,6 @@ HttpHandle HttpRequest::requestSpin(int mode)
 	return handle;
 }
 
-// ====================================
-// Dynamic Policy Methods
-// ====================================
-
-HttpHandle HttpRequest::requestSetHttpProxy(const std::string & proxy, HttpHandler * handler)
-{
-	HttpStatus status;
-	HttpHandle handle(LLCORE_HTTP_HANDLE_INVALID);
-
-	HttpOpSetGet * op = new HttpOpSetGet();
-	op->setupSet(GP_HTTP_PROXY, proxy);
-	op->setReplyPath(mReplyQueue, handler);
-	if (! (status = mRequestQueue->addOp(op)))			// transfers refcount
-	{
-		op->release();
-		mLastReqStatus = status;
-		return handle;
-	}
-
-	mLastReqStatus = status;
-	handle = static_cast<HttpHandle>(op);
-
-	return handle;
-}
-
 
 }   // end namespace LLCore
 
diff --git a/indra/llcorehttp/httprequest.h b/indra/llcorehttp/httprequest.h
index ab2f302d34..651654844a 100755
--- a/indra/llcorehttp/httprequest.h
+++ b/indra/llcorehttp/httprequest.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -56,6 +56,9 @@ class BufferArray;
 /// The class supports the current HTTP request operations:
 ///
 /// - requestGetByteRange:  GET with Range header for a single range of bytes
+/// - requestGet:
+/// - requestPost:
+/// - requestPut:
 ///
 /// Policy Classes
 ///
@@ -100,9 +103,26 @@ public:
 
 	/// Represents a default, catch-all policy class that guarantees
 	/// eventual service for any HTTP request.
-	static const int DEFAULT_POLICY_ID = 0;
+	static const policy_t DEFAULT_POLICY_ID = 0;
+	static const policy_t INVALID_POLICY_ID = 0xFFFFFFFFU;
+	static const policy_t GLOBAL_POLICY_ID = 0xFFFFFFFEU;
 
-	enum EGlobalPolicy
+	/// Create a new policy class into which requests can be made.
+	///
+	/// All class creation must occur before threads are started and
+	/// transport begins.  Policy classes are limited to a small value.
+	/// Currently that limit is the default class + 1.
+	///
+	/// @return			If positive, the policy_id used to reference
+	///					the class in other methods.  If 0, requests
+	///					for classes have exceeded internal limits
+	///					or caller has tried to create a class after
+	///					threads have been started.  Caller must fallback
+	///					and recover.
+	///
+	static policy_t createPolicyClass();
+
+	enum EPolicyOption
 	{
 		/// Maximum number of connections the library will use to
 		/// perform operations.  This is somewhat soft as the underlying
@@ -113,24 +133,40 @@ public:
 		/// a somewhat soft value.  There may be an additional five
 		/// connections per policy class depending upon runtime
 		/// behavior.
-		GP_CONNECTION_LIMIT,
+		///
+		/// Both global and per-class
+		PO_CONNECTION_LIMIT,
+
+		/// Limits the number of connections used for a single
+		/// literal address/port pair within the class.
+		///
+		/// Per-class only
+		PO_PER_HOST_CONNECTION_LIMIT,
 
 		/// String containing a system-appropriate directory name
 		/// where SSL certs are stored.
-		GP_CA_PATH,
+		///
+		/// Global only
+		PO_CA_PATH,
 
 		/// String giving a full path to a file containing SSL certs.
-		GP_CA_FILE,
+		///
+		/// Global only
+		PO_CA_FILE,
 
 		/// String of host/port to use as simple HTTP proxy.  This is
 		/// going to change in the future into something more elaborate
 		/// that may support richer schemes.
-		GP_HTTP_PROXY,
+		///
+		/// Global only
+		PO_HTTP_PROXY,
 
 		/// Long value that if non-zero enables the use of the
 		/// traditional LLProxy code for http/socks5 support.  If
-		/// enabled, has priority over GP_HTTP_PROXY.
-		GP_LLPROXY,
+		// enabled, has priority over GP_HTTP_PROXY.
+		///
+		/// Global only
+		PO_LLPROXY,
 
 		/// Long value setting the logging trace level for the
 		/// library.  Possible values are:
@@ -143,50 +179,59 @@ public:
 		/// These values are also used in the trace modes for
 		/// individual requests in HttpOptions.  Also be aware that
 		/// tracing tends to impact performance of the viewer.
-		GP_TRACE
-	};
-
-	/// Set a parameter on a global policy option.  Calls
-	/// made after the start of the servicing thread are
-	/// not honored and return an error status.
-	///
-	/// @param opt		Enum of option to be set.
-	/// @param value	Desired value of option.
-	/// @return			Standard status code.
-	static HttpStatus setPolicyGlobalOption(EGlobalPolicy opt, long value);
-	static HttpStatus setPolicyGlobalOption(EGlobalPolicy opt, const std::string & value);
-
-	/// Create a new policy class into which requests can be made.
-	///
-	/// @return			If positive, the policy_id used to reference
-	///					the class in other methods.  If 0, an error
-	///					occurred and @see getStatus() may provide more
-	///					detail on the reason.
-	static policy_t createPolicyClass();
-
-	enum EClassPolicy
-	{
-		/// Limits the number of connections used for the class.
-		CP_CONNECTION_LIMIT,
-
-		/// Limits the number of connections used for a single
-		/// literal address/port pair within the class.
-		CP_PER_HOST_CONNECTION_LIMIT,
+		///
+		/// Global only
+		PO_TRACE,
 
 		/// Suitable requests are allowed to pipeline on their
 		/// connections when they ask for it.
-		CP_ENABLE_PIPELINING
+		///
+		/// Per-class only
+		PO_ENABLE_PIPELINING,
+
+		/// Controls whether client-side throttling should be
+		/// performed on this policy class.  Positive values
+		/// enable throttling and specify the request rate
+		/// (requests per second) that should be targetted.
+		/// A value of zero, the default, specifies no throttling.
+		///
+		/// Per-class only
+		PO_THROTTLE_RATE,
+		
+		PO_LAST  // Always at end
 	};
-	
+
+	/// Set a policy option for a global or class parameter at
+	/// startup time (prior to thread start).
+	///
+	/// @param opt			Enum of option to be set.
+	/// @param pclass		For class-based options, the policy class ID to
+	///					    be changed.  For globals, specify GLOBAL_POLICY_ID.
+	/// @param value		Desired value of option.
+	/// @param ret_value	Pointer to receive effective set value
+	///						if successful.  May be NULL if effective
+	///						value not wanted.
+	/// @return				Standard status code.
+	static HttpStatus setStaticPolicyOption(EPolicyOption opt, policy_t pclass,
+											long value, long * ret_value);
+	static HttpStatus setStaticPolicyOption(EPolicyOption opt, policy_t pclass,
+											const std::string & value, std::string * ret_value);
+
 	/// Set a parameter on a class-based policy option.  Calls
 	/// made after the start of the servicing thread are
 	/// not honored and return an error status.
 	///
-	/// @param policy_id		ID of class as returned by @see createPolicyClass().
-	/// @param opt				Enum of option to be set.
-	/// @param value			Desired value of option.
-	/// @return					Standard status code.
-	static HttpStatus setPolicyClassOption(policy_t policy_id, EClassPolicy opt, long value);
+	/// @param opt			Enum of option to be set.
+	/// @param pclass		For class-based options, the policy class ID to
+	///					    be changed.  Ignored for globals but recommend
+	///					    using INVALID_POLICY_ID in this case.
+	/// @param value		Desired value of option.
+	/// @return				Handle of dynamic request.  Use @see getStatus() if
+	///						the returned handle is invalid.
+	HttpHandle setPolicyOption(EPolicyOption opt, policy_t pclass, long value,
+							   HttpHandler * handler);
+	HttpHandle setPolicyOption(EPolicyOption opt, policy_t pclass, const std::string & value,
+							   HttpHandler * handler);
 
 	/// @}
 
@@ -488,16 +533,6 @@ public:
 
 	/// @}
 	
-	/// @name DynamicPolicyMethods
-	///
-	/// @{
-
-	/// Request that a running transport pick up a new proxy setting.
-	/// An empty string will indicate no proxy is to be used.
-	HttpHandle requestSetHttpProxy(const std::string & proxy, HttpHandler * handler);
-
-    /// @}
-
 protected:
 	void generateNotification(HttpOperation * op);
 
@@ -519,7 +554,6 @@ private:
 	/// Must be established before any threading is allowed to
 	/// start.
 	///
-	static policy_t		sNextPolicyID;
 	
 	/// @}
 	// End Global State
diff --git a/indra/llcorehttp/httpresponse.cpp b/indra/llcorehttp/httpresponse.cpp
index a552e48a1b..c974395b0a 100755
--- a/indra/llcorehttp/httpresponse.cpp
+++ b/indra/llcorehttp/httpresponse.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -39,7 +39,9 @@ HttpResponse::HttpResponse()
 	  mReplyLength(0U),
 	  mReplyFullLength(0U),
 	  mBufferArray(NULL),
-	  mHeaders(NULL)
+	  mHeaders(NULL),
+	  mRetries(0U),
+	  m503Retries(0U)
 {}
 
 
diff --git a/indra/llcorehttp/httpresponse.h b/indra/llcorehttp/httpresponse.h
index f19b521fbf..aee64e2878 100755
--- a/indra/llcorehttp/httpresponse.h
+++ b/indra/llcorehttp/httpresponse.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -149,6 +149,25 @@ public:
 			mContentType = con_type;
 		}
 
+	/// Get and set retry attempt information on the request.
+	void getRetries(unsigned int * retries, unsigned int * retries_503) const
+		{
+			if (retries)
+			{
+				*retries = mRetries;
+			}
+			if (retries_503)
+			{
+				*retries_503 = m503Retries;
+			}
+		}
+
+	void setRetries(unsigned int retries, unsigned int retries_503)
+		{
+			mRetries = retries;
+			m503Retries = retries_503;
+		}
+
 protected:
 	// Response data here
 	HttpStatus			mStatus;
@@ -158,6 +177,8 @@ protected:
 	BufferArray *		mBufferArray;
 	HttpHeaders *		mHeaders;
 	std::string			mContentType;
+	unsigned int		mRetries;
+	unsigned int		m503Retries;
 };
 
 
diff --git a/indra/llcorehttp/tests/test_httprequest.hpp b/indra/llcorehttp/tests/test_httprequest.hpp
index 0f0876b467..43f7e36da5 100755
--- a/indra/llcorehttp/tests/test_httprequest.hpp
+++ b/indra/llcorehttp/tests/test_httprequest.hpp
@@ -1222,7 +1222,7 @@ void HttpRequestTestObjectType::test<12>()
 		HttpRequest::createService();
 
 		// Enable tracing
-		HttpRequest::setPolicyGlobalOption(LLCore::HttpRequest::GP_TRACE, 2);
+		HttpRequest::setStaticPolicyOption(HttpRequest::PO_TRACE, HttpRequest::DEFAULT_POLICY_ID, 2, NULL);
 
 		// Start threading early so that thread memory is invariant
 		// over the test.
@@ -1340,7 +1340,7 @@ void HttpRequestTestObjectType::test<13>()
 		HttpRequest::createService();
 
 		// Enable tracing
-		HttpRequest::setPolicyGlobalOption(LLCore::HttpRequest::GP_TRACE, 2);
+		HttpRequest::setStaticPolicyOption(HttpRequest::PO_TRACE, HttpRequest::DEFAULT_POLICY_ID, 2, NULL);
 
 		// Start threading early so that thread memory is invariant
 		// over the test.
@@ -3175,6 +3175,142 @@ void HttpRequestTestObjectType::test<22>()
 	}
 }
 
+template <> template <>
+void HttpRequestTestObjectType::test<23>()
+{
+	ScopedCurlInit ready;
+
+	set_test_name("HttpRequest GET 503s with 'Retry-After'");
+
+	// This tests mainly that the code doesn't fall over if
+	// various well- and mis-formed Retry-After headers are
+	// sent along with the response.  Direct inspection of
+	// the parsing result isn't supported.
+	
+	// Handler can be stack-allocated *if* there are no dangling
+	// references to it after completion of this method.
+	// Create before memory record as the string copy will bump numbers.
+	TestHandler2 handler(this, "handler");
+	std::string url_base(get_base_url() + "/503/");	// path to 503 generators
+		
+	// record the total amount of dynamically allocated memory
+	mMemTotal = GetMemTotal();
+	mHandlerCalls = 0;
+
+	HttpRequest * req = NULL;
+	HttpOptions * opts = NULL;
+	
+	try
+	{
+		// Get singletons created
+		HttpRequest::createService();
+		
+		// Start threading early so that thread memory is invariant
+		// over the test.
+		HttpRequest::startThread();
+
+		// create a new ref counted object with an implicit reference
+		req = new HttpRequest();
+		ensure("Memory allocated on construction", mMemTotal < GetMemTotal());
+
+		opts = new HttpOptions();
+		opts->setRetries(1);			// Retry once only
+		opts->setUseRetryAfter(true);	// Try to parse the retry-after header
+		
+		// Issue a GET that 503s with valid retry-after
+		mStatus = HttpStatus(503);
+		int url_limit(6);
+		for (int i(0); i < url_limit; ++i)
+		{
+			std::ostringstream url;
+			url << url_base << i << "/";
+			HttpHandle handle = req->requestGetByteRange(HttpRequest::DEFAULT_POLICY_ID,
+														 0U,
+														 url.str(),
+														 0,
+														 0,
+														 opts,
+														 NULL,
+														 &handler);
+
+			std::ostringstream testtag;
+			testtag << "Valid handle returned for 503 request #" << i;
+			ensure(testtag.str(), handle != LLCORE_HTTP_HANDLE_INVALID);
+		}
+		
+
+		// Run the notification pump.
+		int count(0);
+		int limit(LOOP_COUNT_LONG);
+		while (count++ < limit && mHandlerCalls < url_limit)
+		{
+			req->update(0);
+			usleep(LOOP_SLEEP_INTERVAL);
+		}
+		ensure("Request executed in reasonable time", count < limit);
+		ensure("One handler invocation for request", mHandlerCalls == url_limit);
+
+		// Okay, request a shutdown of the servicing thread
+		mStatus = HttpStatus();
+		mHandlerCalls = 0;
+		HttpHandle handle = req->requestStopThread(&handler);
+		ensure("Valid handle returned for second request", handle != LLCORE_HTTP_HANDLE_INVALID);
+	
+		// Run the notification pump again
+		count = 0;
+		limit = LOOP_COUNT_LONG;
+		while (count++ < limit && mHandlerCalls < 1)
+		{
+			req->update(1000000);
+			usleep(LOOP_SLEEP_INTERVAL);
+		}
+		ensure("Second request executed in reasonable time", count < limit);
+		ensure("Second handler invocation", mHandlerCalls == 1);
+
+		// See that we actually shutdown the thread
+		count = 0;
+		limit = LOOP_COUNT_SHORT;
+		while (count++ < limit && ! HttpService::isStopped())
+		{
+			usleep(LOOP_SLEEP_INTERVAL);
+		}
+		ensure("Thread actually stopped running", HttpService::isStopped());
+
+		// release options
+		opts->release();
+		opts = NULL;
+		
+		// release the request object
+		delete req;
+		req = NULL;
+
+		// Shut down service
+		HttpRequest::destroyService();
+	
+#if defined(WIN32)
+		// Can only do this memory test on Windows.  On other platforms,
+		// the LL logging system holds on to memory and produces what looks
+		// like memory leaks...
+	
+		// printf("Old mem:  %d, New mem:  %d\n", mMemTotal, GetMemTotal());
+		ensure("Memory usage back to that at entry", mMemTotal == GetMemTotal());
+#endif
+	}
+	catch (...)
+	{
+		stop_thread(req);
+		if (opts)
+		{
+			opts->release();
+			opts = NULL;
+		}
+		delete req;
+		HttpRequest::destroyService();
+		throw;
+	}
+}
+
+
 }  // end namespace tut
 
 namespace
diff --git a/indra/llcorehttp/tests/test_httpstatus.hpp b/indra/llcorehttp/tests/test_httpstatus.hpp
index b5538528c5..0b379836c9 100755
--- a/indra/llcorehttp/tests/test_httpstatus.hpp
+++ b/indra/llcorehttp/tests/test_httpstatus.hpp
@@ -259,6 +259,65 @@ void HttpStatusTestObjectType::test<7>()
 	ensure(msg == "Unknown error");
 }
 
+
+template <> template <>
+void HttpStatusTestObjectType::test<8>()
+{
+	set_test_name("HttpStatus toHex() nominal function");
+	
+	HttpStatus status(404);
+	std::string msg = status.toHex();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure(msg == "01940001");
+}
+
+
+template <> template <>
+void HttpStatusTestObjectType::test<9>()
+{
+	set_test_name("HttpStatus toTerseString() nominal function");
+	
+	HttpStatus status(404);
+	std::string msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Normal HTTP 404", msg == "Http_404");
+
+	status = HttpStatus(200);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Normal HTTP 200", msg == "Http_200");
+
+	status = HttpStatus(200, HE_REPLY_ERROR);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Unsuccessful HTTP 200", msg == "Http_200");			// No distinction for error
+
+	status = HttpStatus(HttpStatus::EXT_CURL_EASY, CURLE_COULDNT_CONNECT);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Easy couldn't connect error", msg == "Easy_7");
+
+	status = HttpStatus(HttpStatus::EXT_CURL_MULTI, CURLM_OUT_OF_MEMORY);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Multi out-of-memory error", msg == "Multi_3");
+
+	status = HttpStatus(HttpStatus::LLCORE, HE_OPT_NOT_SET);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Core option not set error", msg == "Core_7");
+
+	status = HttpStatus(22000, 1);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Undecodable error", msg == "Unknown_1");
+
+	status = HttpStatus(22000, -1);
+	msg = status.toTerseString();
+	// std::cout << "Result:  " << msg << std::endl;
+	ensure("Undecodable error 65535", msg == "Unknown_65535");
+}
+
 } // end namespace tut
 
 #endif	// TEST_HTTP_STATUS_H
diff --git a/indra/llcorehttp/tests/test_llcorehttp_peer.py b/indra/llcorehttp/tests/test_llcorehttp_peer.py
index 3c3af8dc75..04cde651c4 100755
--- a/indra/llcorehttp/tests/test_llcorehttp_peer.py
+++ b/indra/llcorehttp/tests/test_llcorehttp_peer.py
@@ -69,6 +69,15 @@ class TestHTTPRequestHandler(BaseHTTPRequestHandler):
                            "Content-Range: bytes 0-75/2983",
                            "Content-Length: 76"
     -- '/bug2295/inv_cont_range/0/'  Generates HE_INVALID_CONTENT_RANGE error in llcorehttp.
+    - '/503/'           Generate 503 responses with various kinds
+                        of 'retry-after' headers
+    -- '/503/0/'            "Retry-After: 2"   
+    -- '/503/1/'            "Retry-After: Thu, 31 Dec 2043 23:59:59 GMT"
+    -- '/503/2/'            "Retry-After: Fri, 31 Dec 1999 23:59:59 GMT"
+    -- '/503/3/'            "Retry-After: "
+    -- '/503/4/'            "Retry-After: (*#*(@*(@(")"
+    -- '/503/5/'            "Retry-After: aklsjflajfaklsfaklfasfklasdfklasdgahsdhgasdiogaioshdgo"
+    -- '/503/6/'            "Retry-After: 1 2 3 4 5 6 7 8 9 10"
 
     Some combinations make no sense, there's no effort to protect
     you from that.
@@ -143,22 +152,40 @@ class TestHTTPRequestHandler(BaseHTTPRequestHandler):
         if "/sleep/" in self.path:
             time.sleep(30)
 
-        if "fail" in self.path:
-            status = data.get("status", 500)
-            # self.responses maps an int status to a (short, long) pair of
-            # strings. We want the longer string. That's why we pass a string
-            # pair to get(): the [1] will select the second string, whether it
-            # came from self.responses or from our default pair.
-            reason = data.get("reason",
-                               self.responses.get(status,
-                                                  ("fail requested",
-                                                   "Your request specified failure status %s "
-                                                   "without providing a reason" % status))[1])
-            debug("fail requested: %s: %r", status, reason)
-            self.send_error(status, reason)
+        if "/503/" in self.path:
+            # Tests for various kinds of 'Retry-After' header parsing
+            body = None
+            if "/503/0/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "2")
+            elif "/503/1/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "Thu, 31 Dec 2043 23:59:59 GMT")
+            elif "/503/2/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "Fri, 31 Dec 1999 23:59:59 GMT")
+            elif "/503/3/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "")
+            elif "/503/4/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "(*#*(@*(@(")
+            elif "/503/5/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "aklsjflajfaklsfaklfasfklasdfklasdgahsdhgasdiogaioshdgo")
+            elif "/503/6/" in self.path:
+                self.send_response(503)
+                self.send_header("retry-after", "1 2 3 4 5 6 7 8 9 10")
+            else:
+                # Unknown request
+                self.send_response(400)
+                body = "Unknown /503/ path in server"
             if "/reflect/" in self.path:
                 self.reflect_headers()
+            self.send_header("Content-type", "text/plain")
             self.end_headers()
+            if body:
+                self.wfile.write(body)
         elif "/bug2295/" in self.path:
             # Test for https://jira.secondlife.com/browse/BUG-2295
             #
@@ -194,8 +221,7 @@ class TestHTTPRequestHandler(BaseHTTPRequestHandler):
             self.end_headers()
             if body:
                 self.wfile.write(body)
-        else:
-            # Normal response path
+        elif "fail" not in self.path:
             data = data.copy()          # we're going to modify
             # Ensure there's a "reply" key in data, even if there wasn't before
             data["reply"] = data.get("reply", llsd.LLSD("success"))
@@ -210,6 +236,22 @@ class TestHTTPRequestHandler(BaseHTTPRequestHandler):
             self.end_headers()
             if withdata:
                 self.wfile.write(response)
+        else:                           # fail requested
+            status = data.get("status", 500)
+            # self.responses maps an int status to a (short, long) pair of
+            # strings. We want the longer string. That's why we pass a string
+            # pair to get(): the [1] will select the second string, whether it
+            # came from self.responses or from our default pair.
+            reason = data.get("reason",
+                               self.responses.get(status,
+                                                  ("fail requested",
+                                                   "Your request specified failure status %s "
+                                                   "without providing a reason" % status))[1])
+            debug("fail requested: %s: %r", status, reason)
+            self.send_error(status, reason)
+            if "/reflect/" in self.path:
+                self.reflect_headers()
+            self.end_headers()
 
     def reflect_headers(self):
         for name in self.headers.keys():
diff --git a/indra/llmessage/llcurl.cpp b/indra/llmessage/llcurl.cpp
index e8c508dcbf..c28494e2c8 100755
--- a/indra/llmessage/llcurl.cpp
+++ b/indra/llmessage/llcurl.cpp
@@ -6,7 +6,7 @@
  *
  * $LicenseInfo:firstyear=2006&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2010, Linden Research, Inc.
+ * Copyright (C) 2010-2013, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -370,9 +370,12 @@ LLCurl::Easy* LLCurl::Easy::getEasy()
 		return NULL;
 	}
 	
-	// set no DNS caching as default for all easy handles. This prevents them adopting a
-	// multi handles cache if they are added to one.
-	CURLcode result = curl_easy_setopt(easy->mCurlEasyHandle, CURLOPT_DNS_CACHE_TIMEOUT, 0);
+	// Enable a brief cache period for now.  This was zero for the longest time
+	// which caused some routers grief and generated unneeded traffic.  For the
+	// threaded resolver, we're using system resolution libraries and non-zero values
+	// are preferred.  The c-ares resolver is another matter and it might not
+	// track server changes as well.
+	CURLcode result = curl_easy_setopt(easy->mCurlEasyHandle, CURLOPT_DNS_CACHE_TIMEOUT, 15);
 	check_curl_code(result);
 	result = curl_easy_setopt(easy->mCurlEasyHandle, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
 	check_curl_code(result);
diff --git a/indra/newview/VIEWER_VERSION.txt b/indra/newview/VIEWER_VERSION.txt
index 0b2eb36f50..c1e43e6d45 100644
--- a/indra/newview/VIEWER_VERSION.txt
+++ b/indra/newview/VIEWER_VERSION.txt
@@ -1 +1 @@
-3.7.2
+3.7.3
diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index 1d62bba39f..75e6c4abb4 100755
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -10068,11 +10068,21 @@
     <key>Value</key>
     <real>16</real>
   </map>
-
+  <key>Mesh2MaxConcurrentRequests</key>
+  <map>
+    <key>Comment</key>
+    <string>Number of connections to use for loading meshes.</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>U32</string>
+    <key>Value</key>
+    <integer>8</integer>
+  </map>
   <key>MeshMaxConcurrentRequests</key>
   <map>
     <key>Comment</key>
-    <string>Number of threads to use for loading meshes.</string>
+    <string>Number of connections to use for loading meshes (legacy system).</string>
     <key>Persist</key>
     <integer>1</integer>
     <key>Type</key>
@@ -10080,6 +10090,28 @@
     <key>Value</key>
     <integer>32</integer>
   </map>
+  <key>MeshUseHttpRetryAfter</key>
+  <map>
+    <key>Comment</key>
+    <string>If TRUE, use Retry-After response headers when rescheduling a mesh request that fails with an HTTP 503 status.  Static.</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>Boolean</string>
+    <key>Value</key>
+    <boolean>1</boolean>
+  </map>
+  <key>MeshUseGetMesh1</key>
+  <map>
+    <key>Comment</key>
+    <string>If TRUE, use the legacy GetMesh capability for mesh download requests.  Semi-dynamic (read at region crossings).</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>Boolean</string>
+    <key>Value</key>
+    <boolean>0</boolean>
+  </map>
    <key>RunMultipleThreads</key>
     <map>
       <key>Comment</key>
diff --git a/indra/newview/llappcorehttp.cpp b/indra/newview/llappcorehttp.cpp
index 0d7d41304d..70dcffefb2 100755
--- a/indra/newview/llappcorehttp.cpp
+++ b/indra/newview/llappcorehttp.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -28,18 +28,81 @@
 
 #include "llappcorehttp.h"
 
+#include "llappviewer.h"
 #include "llviewercontrol.h"
 
 
+// Here is where we begin to get our connection usage under control.
+// This establishes llcorehttp policy classes that, among other
+// things, limit the maximum number of connections to outside
+// services.  Each of the entries below maps to a policy class and
+// has a limit, sometimes configurable, of how many connections can
+// be open at a time.
+
 const F64 LLAppCoreHttp::MAX_THREAD_WAIT_TIME(10.0);
+static const struct
+{
+	LLAppCoreHttp::EAppPolicy	mPolicy;
+	U32							mDefault;
+	U32							mMin;
+	U32							mMax;
+	U32							mRate;
+	std::string					mKey;
+	const char *				mUsage;
+} init_data[] =					//  Default and dynamic values for classes
+{
+	{
+		LLAppCoreHttp::AP_DEFAULT,			8,		8,		8,		0,
+		"",
+		"other"
+	},
+	{
+		LLAppCoreHttp::AP_TEXTURE,			8,		1,		12,		0,
+		"TextureFetchConcurrency",
+		"texture fetch"
+	},
+	{
+		LLAppCoreHttp::AP_MESH1,			32,		1,		128,	100,
+		"MeshMaxConcurrentRequests",
+		"mesh fetch"
+	},
+	{
+		LLAppCoreHttp::AP_MESH2,			8,		1,		32,		100,
+		"Mesh2MaxConcurrentRequests",
+		"mesh2 fetch"
+	},
+	{
+		LLAppCoreHttp::AP_LARGE_MESH,		2,		1,		8,		0,
+		"",
+		"large mesh fetch"
+	},
+	{
+		LLAppCoreHttp::AP_UPLOADS,			2,		1,		8,		0,
+		"",
+		"asset upload"
+	},
+	{
+		LLAppCoreHttp::AP_LONG_POLL,		32,		32,		32,		0,
+		"",
+		"long poll"
+	}
+};
+
+static void setting_changed();
+
 
 LLAppCoreHttp::LLAppCoreHttp()
 	: mRequest(NULL),
 	  mStopHandle(LLCORE_HTTP_HANDLE_INVALID),
 	  mStopRequested(0.0),
-	  mStopped(false),
-	  mPolicyDefault(-1)
-{}
+	  mStopped(false)
+{
+	for (int i(0); i < LL_ARRAY_SIZE(mPolicies); ++i)
+	{
+		mPolicies[i] = LLCore::HttpRequest::DEFAULT_POLICY_ID;
+		mSettings[i] = 0U;
+	}
+}
 
 
 LLAppCoreHttp::~LLAppCoreHttp()
@@ -54,30 +117,28 @@ void LLAppCoreHttp::init()
 	LLCore::HttpStatus status = LLCore::HttpRequest::createService();
 	if (! status)
 	{
-		LL_ERRS("Init") << "Failed to initialize HTTP services.  Reason:  "
-						<< status.toString()
+		LL_ERRS("Init") << "Failed to initialize HTTP services.  Reason:  " << status.toString()
 						<< LL_ENDL;
 	}
 
 	// Point to our certs or SSH/https: will fail on connect
-	status = LLCore::HttpRequest::setPolicyGlobalOption(LLCore::HttpRequest::GP_CA_FILE,
-														gDirUtilp->getCAFile());
+	status = LLCore::HttpRequest::setStaticPolicyOption(LLCore::HttpRequest::PO_CA_FILE,
+														LLCore::HttpRequest::GLOBAL_POLICY_ID,
+														gDirUtilp->getCAFile(), NULL);
 	if (! status)
 	{
-		LL_ERRS("Init") << "Failed to set CA File for HTTP services.  Reason:  "
-						<< status.toString()
+		LL_ERRS("Init") << "Failed to set CA File for HTTP services.  Reason:  " << status.toString()
 						<< LL_ENDL;
 	}
 
-	// Establish HTTP Proxy.  "LLProxy" is a special string which directs
-	// the code to use LLProxy::applyProxySettings() to establish any
-	// HTTP or SOCKS proxy for http operations.
-	status = LLCore::HttpRequest::setPolicyGlobalOption(LLCore::HttpRequest::GP_LLPROXY, 1);
+	// Establish HTTP Proxy, if desired.
+	status = LLCore::HttpRequest::setStaticPolicyOption(LLCore::HttpRequest::PO_LLPROXY,
+														LLCore::HttpRequest::GLOBAL_POLICY_ID,
+														1, NULL);
 	if (! status)
 	{
-		LL_ERRS("Init") << "Failed to set HTTP proxy for HTTP services.  Reason:  "
-						<< status.toString()
-						<< LL_ENDL;
+		LL_WARNS("Init") << "Failed to set HTTP proxy for HTTP services.  Reason:  " << status.toString()
+						 << LL_ENDL;
 	}
 
 	// Tracing levels for library & libcurl (note that 2 & 3 are beyond spammy):
@@ -90,47 +151,74 @@ void LLAppCoreHttp::init()
 	{
 		long trace_level(0L);
 		trace_level = long(gSavedSettings.getU32(http_trace));
-		status = LLCore::HttpRequest::setPolicyGlobalOption(LLCore::HttpRequest::GP_TRACE, trace_level);
+		status = LLCore::HttpRequest::setStaticPolicyOption(LLCore::HttpRequest::PO_TRACE,
+															LLCore::HttpRequest::GLOBAL_POLICY_ID,
+															trace_level, NULL);
 	}
 	
 	// Setup default policy and constrain if directed to
-	mPolicyDefault = LLCore::HttpRequest::DEFAULT_POLICY_ID;
-	static const std::string texture_concur("TextureFetchConcurrency");
-	if (gSavedSettings.controlExists(texture_concur))
+	mPolicies[AP_DEFAULT] = LLCore::HttpRequest::DEFAULT_POLICY_ID;
+
+	// Setup additional policies based on table and some special rules
+	for (int i(0); i < LL_ARRAY_SIZE(init_data); ++i)
 	{
-		U32 concur(llmin(gSavedSettings.getU32(texture_concur), U32(12)));
+		const EAppPolicy policy(init_data[i].mPolicy);
 
-		if (concur > 0)
+		if (AP_DEFAULT == policy)
 		{
-			LLCore::HttpStatus status;
-			status = LLCore::HttpRequest::setPolicyClassOption(mPolicyDefault,
-															   LLCore::HttpRequest::CP_CONNECTION_LIMIT,
-															   concur);
-			if (! status)
-			{
-				LL_WARNS("Init") << "Unable to set texture fetch concurrency.  Reason:  "
-								 << status.toString()
-								 << LL_ENDL;
-			}
-			else
-			{
-				LL_INFOS("Init") << "Application settings overriding default texture fetch concurrency.  New value:  "
-								 << concur
-								 << LL_ENDL;
-			}
+			// Pre-created
+			continue;
+		}
+
+		mPolicies[policy] = LLCore::HttpRequest::createPolicyClass();
+		if (! mPolicies[policy])
+		{
+			// Use default policy (but don't accidentally modify default)
+			LL_WARNS("Init") << "Failed to create HTTP policy class for " << init_data[i].mUsage
+							 << ".  Using default policy."
+							 << LL_ENDL;
+			mPolicies[policy] = mPolicies[AP_DEFAULT];
+			continue;
 		}
 	}
+
+	// Need a request object to handle dynamic options before setting them
+	mRequest = new LLCore::HttpRequest;
+
+	// Apply initial settings
+	refreshSettings(true);
 	
 	// Kick the thread
 	status = LLCore::HttpRequest::startThread();
 	if (! status)
 	{
-		LL_ERRS("Init") << "Failed to start HTTP servicing thread.  Reason:  "
-						<< status.toString()
+		LL_ERRS("Init") << "Failed to start HTTP servicing thread.  Reason:  " << status.toString()
 						<< LL_ENDL;
 	}
 
-	mRequest = new LLCore::HttpRequest;
+	// Register signals for settings and state changes
+	for (int i(0); i < LL_ARRAY_SIZE(init_data); ++i)
+	{
+		if (! init_data[i].mKey.empty() && gSavedSettings.controlExists(init_data[i].mKey))
+		{
+			LLPointer<LLControlVariable> cntrl_ptr = gSavedSettings.getControl(init_data[i].mKey);
+			if (cntrl_ptr.isNull())
+			{
+				LL_WARNS("Init") << "Unable to set signal on global setting '" << init_data[i].mKey
+								 << "'" << LL_ENDL;
+			}
+			else
+			{
+				mSettingsSignal[i] = cntrl_ptr->getCommitSignal()->connect(boost::bind(&setting_changed));
+			}
+		}
+	}
+}
+
+
+void setting_changed()
+{
+	LLAppViewer::instance()->getAppCoreHttp().refreshSettings(false);
 }
 
 
@@ -173,6 +261,11 @@ void LLAppCoreHttp::cleanup()
 		}
 	}
 
+	for (int i(0); i < LL_ARRAY_SIZE(init_data); ++i)
+	{
+		mSettingsSignal[i].disconnect();
+	}
+	
 	delete mRequest;
 	mRequest = NULL;
 
@@ -185,6 +278,78 @@ void LLAppCoreHttp::cleanup()
 	}
 }
 
+void LLAppCoreHttp::refreshSettings(bool initial)
+{
+	LLCore::HttpStatus status;
+	
+	for (int i(0); i < LL_ARRAY_SIZE(init_data); ++i)
+	{
+		const EAppPolicy policy(init_data[i].mPolicy);
+
+		// Set any desired throttle
+		if (initial && init_data[i].mRate)
+		{
+			// Init-time only, can use the static setters here
+			status = LLCore::HttpRequest::setStaticPolicyOption(LLCore::HttpRequest::PO_THROTTLE_RATE,
+																mPolicies[policy],
+																init_data[i].mRate,
+																NULL);
+			if (! status)
+			{
+				LL_WARNS("Init") << "Unable to set " << init_data[i].mUsage
+								 << " throttle rate.  Reason:  " << status.toString()
+								 << LL_ENDL;
+			}
+		}
+
+		// Get target connection concurrency value
+		U32 setting(init_data[i].mDefault);
+		if (! init_data[i].mKey.empty() && gSavedSettings.controlExists(init_data[i].mKey))
+		{
+			U32 new_setting(gSavedSettings.getU32(init_data[i].mKey));
+			if (new_setting)
+			{
+				// Treat zero settings as an ask for default
+				setting = llclamp(new_setting, init_data[i].mMin, init_data[i].mMax);
+			}
+		}
+
+		if (! initial && setting == mSettings[policy])
+		{
+			// Unchanged, try next setting
+			continue;
+		}
+		
+		// Set it and report
+		// *TODO:  These are intended to be per-host limits when we can
+		// support that in llcorehttp/libcurl.
+		LLCore::HttpHandle handle;
+		handle = mRequest->setPolicyOption(LLCore::HttpRequest::PO_CONNECTION_LIMIT,
+										   mPolicies[policy],
+										   setting, NULL);
+		if (LLCORE_HTTP_HANDLE_INVALID == handle)
+		{
+			status = mRequest->getStatus();
+			LL_WARNS("Init") << "Unable to set " << init_data[i].mUsage
+							 << " concurrency.  Reason:  " << status.toString()
+							 << LL_ENDL;
+		}
+		else
+		{
+			LL_DEBUGS("Init") << "Changed " << init_data[i].mUsage
+							  << " concurrency.  New value:  " << setting
+							  << LL_ENDL;
+			mSettings[policy] = setting;
+			if (initial && setting != init_data[i].mDefault)
+			{
+				LL_INFOS("Init") << "Application settings overriding default " << init_data[i].mUsage
+								 << " concurrency.  New value:  " << setting
+								 << LL_ENDL;
+			}
+		}
+	}
+}
+
 
 void LLAppCoreHttp::onCompleted(LLCore::HttpHandle, LLCore::HttpResponse *)
 {
diff --git a/indra/newview/llappcorehttp.h b/indra/newview/llappcorehttp.h
index 241d73ad52..40e3042b84 100755
--- a/indra/newview/llappcorehttp.h
+++ b/indra/newview/llappcorehttp.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2012&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -41,6 +41,117 @@
 class LLAppCoreHttp : public LLCore::HttpHandler
 {
 public:
+	typedef LLCore::HttpRequest::policy_t policy_t;
+
+	enum EAppPolicy
+	{
+		/// Catchall policy class.  Not used yet
+		/// but will have a generous concurrency
+		/// limit.  Deep queueing possible by having
+		/// a chatty HTTP user.
+		///
+		/// Destination:     anywhere
+		/// Protocol:        http: or https:
+		/// Transfer size:   KB-MB
+		/// Long poll:       no
+		/// Concurrency:     high 
+		/// Request rate:    unknown
+		/// Pipelined:       no
+		AP_DEFAULT,
+
+		/// Texture fetching policy class.  Used to
+		/// download textures via capability or SSA
+		/// baking service.  Deep queueing of requests.
+		/// Do not share.
+		///
+		/// Destination:     simhost:12046 & bake-texture:80
+		/// Protocol:        http:
+		/// Transfer size:   KB-MB
+		/// Long poll:       no
+		/// Concurrency:     high
+		/// Request rate:    high
+		/// Pipelined:       soon
+		AP_TEXTURE,
+
+		/// Legacy mesh fetching policy class.  Used to
+		/// download textures via 'GetMesh' capability.
+		/// To be deprecated.  Do not share.
+		///
+		/// Destination:     simhost:12046
+		/// Protocol:        http:
+		/// Transfer size:   KB-MB
+		/// Long poll:       no
+		/// Concurrency:     dangerously high
+		/// Request rate:    high
+		/// Pipelined:       no
+		AP_MESH1,
+
+		/// New mesh fetching policy class.  Used to
+		/// download textures via 'GetMesh2' capability.
+		/// Used when fetch request (typically one LOD)
+		/// is 'small', currently defined as 2MB.
+		/// Very deeply queued.  Do not share.
+		///
+		/// Destination:     simhost:12046
+		/// Protocol:        http:
+		/// Transfer size:   KB-MB
+		/// Long poll:       no
+		/// Concurrency:     high
+		/// Request rate:    high
+		/// Pipelined:       soon
+		AP_MESH2,
+
+		/// Large mesh fetching policy class.  Used to
+		/// download textures via 'GetMesh' or 'GetMesh2'
+		/// capability.  Used when fetch request
+		/// is not small to avoid head-of-line problem
+		/// when large requests block a sequence of small,
+		/// fast requests.  Can be shared with similar
+		/// traffic that can wait for longish stalls
+		/// (default timeout 600S).
+		///
+		/// Destination:     simhost:12046
+		/// Protocol:        http:
+		/// Transfer size:   MB
+		/// Long poll:       no
+		/// Concurrency:     low
+		/// Request rate:    low
+		/// Pipelined:       soon
+		AP_LARGE_MESH,
+
+		/// Asset upload policy class.  Used to store
+		/// assets (mesh only at the moment) via
+		/// changeable URL.  Responses may take some
+		/// time (default timeout 240S).
+		///
+		/// Destination:     simhost:12043
+		/// Protocol:        https:
+		/// Transfer size:   KB-MB
+		/// Long poll:       no
+		/// Concurrency:     low
+		/// Request rate:    low
+		/// Pipelined:       no
+		AP_UPLOADS,
+
+		/// Long-poll-type HTTP requests.  Not
+		/// bound by a connection limit.  Requests
+		/// will typically hang around for a long
+		/// time (~30S).  Only shareable with other
+		/// long-poll requests.
+		///
+		/// Destination:     simhost:12043
+		/// Protocol:        https:
+		/// Transfer size:   KB
+		/// Long poll:       yes
+		/// Concurrency:     unlimited but low in practice
+		/// Request rate:    low
+		/// Pipelined:       no
+		AP_LONG_POLL,
+
+		AP_COUNT						// Must be last
+	};
+	
+public:
 	LLAppCoreHttp();
 	~LLAppCoreHttp();
 	
@@ -65,21 +176,27 @@ public:
 	// Notification when the stop request is complete.
 	virtual void onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response);
 
-	// Retrieve the policy class for default operations.
-	int getPolicyDefault() const
+	// Retrieve a policy class identifier for desired
+	// application function.
+	policy_t getPolicy(EAppPolicy policy) const
 		{
-			return mPolicyDefault;
+			return mPolicies[policy];
 		}
+
+	// Apply initial or new settings from the environment.
+	void refreshSettings(bool initial);
 	
 private:
 	static const F64			MAX_THREAD_WAIT_TIME;
 	
 private:
-	LLCore::HttpRequest *		mRequest;
+	LLCore::HttpRequest *		mRequest;						// Request queue to issue shutdowns
 	LLCore::HttpHandle			mStopHandle;
 	F64							mStopRequested;
 	bool						mStopped;
-	int							mPolicyDefault;
+	policy_t					mPolicies[AP_COUNT];			// Policy class id for each connection set
+	U32							mSettings[AP_COUNT];
+	boost::signals2::connection mSettingsSignal[AP_COUNT];		// Signals to global settings that affect us
 };
 
 
diff --git a/indra/newview/llmeshrepository.cpp b/indra/newview/llmeshrepository.cpp
index ff4d96eb54..269c361754 100755
--- a/indra/newview/llmeshrepository.cpp
+++ b/indra/newview/llmeshrepository.cpp
@@ -5,7 +5,7 @@
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2010, Linden Research, Inc.
+ * Copyright (C) 2010-2014, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -38,11 +38,13 @@
 #include "llcallbacklist.h"
 #include "llcurl.h"
 #include "lldatapacker.h"
+#include "lldeadmantimer.h"
 #include "llfloatermodelpreview.h"
 #include "llfloaterperms.h"
 #include "lleconomy.h"
 #include "llimagej2c.h"
 #include "llhost.h"
+#include "llmath.h"
 #include "llnotificationsutil.h"
 #include "llsd.h"
 #include "llsdutil_math.h"
@@ -52,6 +54,7 @@
 #include "llviewercontrol.h"
 #include "llviewerinventory.h"
 #include "llviewermenufile.h"
+#include "llviewermessage.h"
 #include "llviewerobjectlist.h"
 #include "llviewerregion.h"
 #include "llviewertexturelist.h"
@@ -65,6 +68,9 @@
 #include "llfoldertype.h"
 #include "llviewerparcelmgr.h"
 #include "lluploadfloaterobservers.h"
+#include "bufferarray.h"
+#include "bufferstream.h"
+#include "llfasttimer.h"
 
 #include "boost/lexical_cast.hpp"
 
@@ -72,11 +78,296 @@
 #include "netdb.h"
 #endif
 
-#include <queue>
+
+// Purpose
+//
+//   The purpose of this module is to provide access between the viewer
+//   and the asset system as regards to mesh objects.
+//
+//   * High-throughput download of mesh assets from servers while
+//     following best industry practices for network profile.
+//   * Reliable expensing and upload of new mesh assets.
+//   * Recovery and retry from errors when appropriate.
+//   * Decomposition of mesh assets for preview and uploads.
+//   * And most important:  all of the above without exposing the
+//     main thread to stalls due to deep processing or thread
+//     locking actions.  In particular, the following operations
+//     on LLMeshRepository are very averse to any stalls:
+//     * loadMesh
+//     * getMeshHeader (For structural details, see:
+//       http://wiki.secondlife.com/wiki/Mesh/Mesh_Asset_Format)
+//     * notifyLoadedMeshes
+//     * getSkinInfo
+//
+// Threads
+//
+//   main     Main rendering thread, very sensitive to locking and other stalls
+//   repo     Overseeing worker thread associated with the LLMeshRepoThread class
+//   decom    Worker thread for mesh decomposition requests
+//   core     HTTP worker thread:  does the work but doesn't intrude here
+//   uploadN  0-N temporary mesh upload threads (0-1 in practice)
+//
+// Sequence of Operations
+//
+//   What follows is a description of the retrieval of one LOD for
+//   a new mesh object.  Work is performed by a series of short, quick
+//   actions distributed over a number of threads.  Each is meant
+//   to proceed without stalling and the whole forms a deep request
+//   pipeline to achieve throughput.  Ellipsis indicates a return
+//   or break in processing which is resumed elsewhere.
+//
+//         main thread         repo thread (run() method)
+//
+//         loadMesh() invoked to request LOD
+//           append LODRequest to mPendingRequests
+//         ...
+//         other mesh requests may be made
+//         ...
+//         notifyLoadedMeshes() invoked to stage work
+//           append HeaderRequest to mHeaderReqQ
+//         ...
+//                             scan mHeaderReqQ
+//                             issue 4096-byte GET for header
+//                             ...
+//                             onCompleted() invoked for GET
+//                               data copied
+//                               headerReceived() invoked
+//                                 LLSD parsed
+//                                 mMeshHeader, mMeshHeaderSize updated
+//                                 scan mPendingLOD for LOD request
+//                                 push LODRequest to mLODReqQ
+//                             ...
+//                             scan mLODReqQ
+//                             fetchMeshLOD() invoked
+//                               issue Byte-Range GET for LOD
+//                             ...
+//                             onCompleted() invoked for GET
+//                               data copied
+//                               lodReceived() invoked
+//                                 unpack data into LLVolume
+//                                 append LoadedMesh to mLoadedQ
+//                             ...
+//         notifyLoadedMeshes() invoked again
+//           scan mLoadedQ
+//           notifyMeshLoaded() for LOD
+//             setMeshAssetLoaded() invoked for system volume
+//             notifyMeshLoaded() invoked for each interested object
+//         ...
+//
+// Mutexes
+//
+//   LLMeshRepository::mMeshMutex
+//   LLMeshRepoThread::mMutex
+//   LLMeshRepoThread::mHeaderMutex
+//   LLMeshRepoThread::mSignal (LLCondition)
+//   LLPhysicsDecomp::mSignal (LLCondition)
+//   LLPhysicsDecomp::mMutex
+//   LLMeshUploadThread::mMutex
+//
+// Mutex Order Rules
+//
+//   1.  LLMeshRepoThread::mMutex before LLMeshRepoThread::mHeaderMutex
+//   2.  LLMeshRepository::mMeshMutex before LLMeshRepoThread::mMutex
+//   (There are more rules, haven't been extracted.)
+//
+// Data Member Access/Locking
+//
+//   Description of how shared access to static and instance data
+//   members is performed.  Each member is followed by the name of
+//   the mutex, if any, covering the data and then a list of data
+//   access models each of which is a triplet of the following form:
+//
+//     {ro, wo, rw}.{main, repo, any}.{mutex, none}
+//     Type of access:  read-only, write-only, read-write.
+//     Accessing thread or 'any'
+//     Relevant mutex held during access (several may be held) or 'none'
+//
+//   A careful eye will notice some unsafe operations.  Many of these
+//   have an alibi of some form.  Several types of alibi are identified
+//   and listed here:
+//
+//     [0]  No alibi.  Probably unsafe.
+//     [1]  Single-writer, self-consistent readers.  Old data must
+//          be tolerated by any reader but data will come true eventually.
+//     [2]  Like [1] but provides a hint about thread state.  These
+//          may be unsafe.
+//     [3]  empty() check outside of lock.  Can me made safish when
+//          done in double-check lock style.  But this depends on
+//          std:: implementation and memory model.
+//     [4]  Appears to be covered by a mutex but doesn't need one.
+//     [5]  Read of a double-checked lock.
+//
+//   So, in addition to documentation, take this as a to-do/review
+//   list and see if you can improve things.  For porters to non-x86
+//   architectures, the weaker memory models will make these platforms
+//   probabilistically more susceptible to hitting race conditions.
+//   True here and in other multi-thread code such as texture fetching.
+//   (Strong memory models make weak programmers.  Weak memory models
+//   make strong programmers.  Ref:  arm, ppc, mips, alpha)
+//
+//   LLMeshRepository:
+//
+//     sBytesReceived                  none            rw.repo.none, ro.main.none [1]
+//     sMeshRequestCount               "
+//     sHTTPRequestCount               "
+//     sHTTPLargeRequestCount          "
+//     sHTTPRetryCount                 "
+//     sHTTPErrorCount                 "
+//     sLODPending                     mMeshMutex [4]  rw.main.mMeshMutex
+//     sLODProcessing                  Repo::mMutex    rw.any.Repo::mMutex
+//     sCacheBytesRead                 none            rw.repo.none, ro.main.none [1]
+//     sCacheBytesWritten              "
+//     sCacheReads                     "
+//     sCacheWrites                    "
+//     mLoadingMeshes                  mMeshMutex [4]  rw.main.none, rw.any.mMeshMutex
+//     mSkinMap                        none            rw.main.none
+//     mDecompositionMap               none            rw.main.none
+//     mPendingRequests                mMeshMutex [4]  rw.main.mMeshMutex
+//     mLoadingSkins                   mMeshMutex [4]  rw.main.mMeshMutex
+//     mPendingSkinRequests            mMeshMutex [4]  rw.main.mMeshMutex
+//     mLoadingDecompositions          mMeshMutex [4]  rw.main.mMeshMutex
+//     mPendingDecompositionRequests   mMeshMutex [4]  rw.main.mMeshMutex
+//     mLoadingPhysicsShapes           mMeshMutex [4]  rw.main.mMeshMutex
+//     mPendingPhysicsShapeRequests    mMeshMutex [4]  rw.main.mMeshMutex
+//     mUploads                        none            rw.main.none (upload thread accessing objects)
+//     mUploadWaitList                 none            rw.main.none (upload thread accessing objects)
+//     mInventoryQ                     mMeshMutex [4]  rw.main.mMeshMutex, ro.main.none [5]
+//     mUploadErrorQ                   mMeshMutex      rw.main.mMeshMutex, rw.any.mMeshMutex
+//     mGetMeshVersion                 none            rw.main.none
+//
+//   LLMeshRepoThread:
+//
+//     sActiveHeaderRequests    mMutex        rw.any.mMutex, ro.repo.none [1]
+//     sActiveLODRequests       mMutex        rw.any.mMutex, ro.repo.none [1]
+//     sMaxConcurrentRequests   mMutex        wo.main.none, ro.repo.none, ro.main.mMutex
+//     mMeshHeader              mHeaderMutex  rw.repo.mHeaderMutex, ro.main.mHeaderMutex, ro.main.none [0]
+//     mMeshHeaderSize          mHeaderMutex  rw.repo.mHeaderMutex
+//     mSkinRequests            mMutex        rw.repo.mMutex, ro.repo.none [5]
+//     mSkinInfoQ               mMutex        rw.repo.mMutex, rw.main.mMutex [5] (was:  [0])
+//     mDecompositionRequests   mMutex        rw.repo.mMutex, ro.repo.none [5]
+//     mPhysicsShapeRequests    mMutex        rw.repo.mMutex, ro.repo.none [5]
+//     mDecompositionQ          mMutex        rw.repo.mMutex, rw.main.mMutex [5] (was:  [0])
+//     mHeaderReqQ              mMutex        ro.repo.none [5], rw.repo.mMutex, rw.any.mMutex
+//     mLODReqQ                 mMutex        ro.repo.none [5], rw.repo.mMutex, rw.any.mMutex
+//     mUnavailableQ            mMutex        rw.repo.none [0], ro.main.none [5], rw.main.mMutex
+//     mLoadedQ                 mMutex        rw.repo.mMutex, ro.main.none [5], rw.main.mMutex
+//     mPendingLOD              mMutex        rw.repo.mMutex, rw.any.mMutex
+//     mGetMeshCapability       mMutex        rw.main.mMutex, ro.repo.mMutex (was:  [0])
+//     mGetMesh2Capability      mMutex        rw.main.mMutex, ro.repo.mMutex (was:  [0])
+//     mGetMeshVersion          mMutex        rw.main.mMutex, ro.repo.mMutex
+//     mHttp*                   none          rw.repo.none
+//
+//   LLMeshUploadThread:
+//
+//     mDiscarded               mMutex        rw.main.mMutex, ro.uploadN.none [1]
+//     ... more ...
+//
+// QA/Development Testing
+//
+//   Debug variable 'MeshUploadFakeErrors' takes a mask of bits that will
+//   simulate an error on fee query or upload.  Defined bits are:
+//
+//   0x01            Simulate application error on fee check reading
+//                   response body from file "fake_upload_error.xml"
+//   0x02            Same as 0x01 but for actual upload attempt.
+//   0x04            Simulate a transport problem on fee check with a
+//                   locally-generated 500 status.
+//   0x08            As with 0x04 but for the upload operation.
+//
+//   For major changes, see the LL_MESH_FASTTIMER_ENABLE below and
+//   instructions for looking for frame stalls using fast timers.
+//
+// *TODO:  Work list for followup actions:
+//   * Review anything marked as unsafe above, verify if there are real issues.
+//   * See if we can put ::run() into a hard sleep.  May not actually perform better
+//     than the current scheme so be prepared for disappointment.  You'll likely
+//     need to introduce a condition variable class that references a mutex in
+//     methods rather than derives from mutex which isn't correct.
+//   * On upload failures, make more information available to the alerting
+//     dialog.  Get the structured information going into the log into a
+//     tree there.
+//   * Header parse failures come without much explanation.  Elaborate.
+//   * Work queue for uploads?  Any need for this or is the current scheme good
+//     enough?
+//   * Various temp buffers used in VFS I/O might be allocated once or even
+//     statically.  Look for some wins here.
+//   * Move data structures holding mesh data used by main thread into main-
+//     thread-only access so that no locking is needed.  May require duplication
+//     of some data so that worker thread has a minimal data set to guide
+//     operations.
+//
+// --------------------------------------------------------------------------
+//                    Development/Debug/QA Tools
+//
+// Enable here or in build environment to get fasttimer data on mesh fetches.
+//
+// Typically, this is used to perform A/B testing using the
+// fasttimer console (shift-ctrl-9).  This is done by looking
+// for stalls due to lock contention between the main thread
+// and the repository and HTTP code.  In a release viewer,
+// these appear as ping-time or worse spikes in frame time.
+// With this instrumentation enabled, a stall will appear
+// under the 'Mesh Fetch' timer which will be either top-level
+// or under 'Render' time.
+
+#ifndef	LL_MESH_FASTTIMER_ENABLE
+#define LL_MESH_FASTTIMER_ENABLE		1
+#endif
+#if LL_MESH_FASTTIMER_ENABLE
+static LLFastTimer::DeclareTimer FTM_MESH_FETCH("Mesh Fetch");
+
+#define	MESH_FASTTIMER_DEFBLOCK			LLFastTimer meshtimer(FTM_MESH_FETCH)
+#else
+#define	MESH_FASTTIMER_DEFBLOCK
+#endif // LL_MESH_FASTTIMER_ENABLE
+
+
+// Random failure testing for development/QA.
+//
+// Set the MESH_*_FAILED macros to either 'false' or to
+// an invocation of MESH_RANDOM_NTH_TRUE() with some
+// suitable number.  In production, all must be false.
+//
+// Example:
+// #define	MESH_HTTP_RESPONSE_FAILED				MESH_RANDOM_NTH_TRUE(9)
+
+// 1-in-N calls will test true
+#define	MESH_RANDOM_NTH_TRUE(_N)				( ll_rand(S32(_N)) == 0 )
+
+#define	MESH_HTTP_RESPONSE_FAILED				false
+#define	MESH_HEADER_PROCESS_FAILED				false
+#define	MESH_LOD_PROCESS_FAILED					false
+#define	MESH_SKIN_INFO_PROCESS_FAILED			false
+#define	MESH_DECOMP_PROCESS_FAILED				false
+#define MESH_PHYS_SHAPE_PROCESS_FAILED			false
+
+// --------------------------------------------------------------------------
+
 
 LLMeshRepository gMeshRepo;
 
-const U32 MAX_MESH_REQUESTS_PER_SECOND = 100;
+const S32 MESH_HEADER_SIZE = 4096;                      // Important:  assumption is that headers fit in this space
+const S32 REQUEST_HIGH_WATER_MIN = 32;					// Limits for GetMesh regions
+const S32 REQUEST_HIGH_WATER_MAX = 150;					// Should remain under 2X throttle
+const S32 REQUEST_LOW_WATER_MIN = 16;
+const S32 REQUEST_LOW_WATER_MAX = 75;
+const S32 REQUEST2_HIGH_WATER_MIN = 32;					// Limits for GetMesh2 regions
+const S32 REQUEST2_HIGH_WATER_MAX = 80;
+const S32 REQUEST2_LOW_WATER_MIN = 16;
+const S32 REQUEST2_LOW_WATER_MAX = 40;
+const U32 LARGE_MESH_FETCH_THRESHOLD = 1U << 21;		// Size at which requests goes to narrow/slow queue
+const long SMALL_MESH_XFER_TIMEOUT = 120L;				// Seconds to complete xfer, small mesh downloads
+const long LARGE_MESH_XFER_TIMEOUT = 600L;				// Seconds to complete xfer, large downloads
+
+// Would normally like to retry on uploads as some
+// retryable failures would be recoverable.  Unfortunately,
+// the mesh service is using 500 (retryable) rather than
+// 400/bad request (permanent) for a bad payload and
+// retrying that just leads to revocation of the one-shot
+// cap which then produces a 404 on retry destroying some
+// (occasionally) useful error information.  We'll leave
+// upload retries to the user as in the past.  SH-4667.
+const long UPLOAD_RETRY_LIMIT = 0L;
 
 // Maximum mesh version to support.  Three least significant digits are reserved for the minor version, 
 // with major version changes indicating a format change that is not backwards compatible and should not
@@ -87,35 +378,45 @@ const U32 MAX_MESH_REQUESTS_PER_SECOND = 100;
 const S32 MAX_MESH_VERSION = 999;
 
 U32 LLMeshRepository::sBytesReceived = 0;
+U32 LLMeshRepository::sMeshRequestCount = 0;
 U32 LLMeshRepository::sHTTPRequestCount = 0;
+U32 LLMeshRepository::sHTTPLargeRequestCount = 0;
 U32 LLMeshRepository::sHTTPRetryCount = 0;
+U32 LLMeshRepository::sHTTPErrorCount = 0;
 U32 LLMeshRepository::sLODProcessing = 0;
 U32 LLMeshRepository::sLODPending = 0;
 
 U32 LLMeshRepository::sCacheBytesRead = 0;
 U32 LLMeshRepository::sCacheBytesWritten = 0;
-U32 LLMeshRepository::sPeakKbps = 0;
-	
+U32 LLMeshRepository::sCacheReads = 0;
+U32 LLMeshRepository::sCacheWrites = 0;
+U32 LLMeshRepository::sMaxLockHoldoffs = 0;
 
-const U32 MAX_TEXTURE_UPLOAD_RETRIES = 5;
+LLDeadmanTimer LLMeshRepository::sQuiescentTimer(15.0, false);	// true -> gather cpu metrics
 
+	
 static S32 dump_num = 0;
 std::string make_dump_name(std::string prefix, S32 num)
 {
 	return prefix + boost::lexical_cast<std::string>(num) + std::string(".xml");
-	
 }
 void dump_llsd_to_file(const LLSD& content, std::string filename);
 LLSD llsd_from_file(std::string filename);
 
-std::string header_lod[] = 
+const std::string header_lod[] = 
 {
 	"lowest_lod",
 	"low_lod",
 	"medium_lod",
 	"high_lod"
 };
+const char * const LOG_MESH = "Mesh";
 
+// Static data and functions to measure mesh load
+// time metrics for a new region scene.
+static unsigned int metrics_teleport_start_count = 0;
+boost::signals2::connection metrics_teleport_started_signal;
+static void teleport_started();
 
 //get the number of bytes resident in memory for given volume
 U32 get_volume_memory_size(const LLVolume* volume)
@@ -197,200 +498,233 @@ void get_vertex_buffer_from_mesh(LLCDMeshData& mesh, LLModel::PhysicsMesh& res,
 	}
 }
 
-S32 LLMeshRepoThread::sActiveHeaderRequests = 0;
-S32 LLMeshRepoThread::sActiveLODRequests = 0;
+volatile S32 LLMeshRepoThread::sActiveHeaderRequests = 0;
+volatile S32 LLMeshRepoThread::sActiveLODRequests = 0;
 U32	LLMeshRepoThread::sMaxConcurrentRequests = 1;
-
-class LLMeshHeaderResponder : public LLCurl::Responder
+S32 LLMeshRepoThread::sRequestLowWater = REQUEST2_LOW_WATER_MIN;
+S32 LLMeshRepoThread::sRequestHighWater = REQUEST2_HIGH_WATER_MIN;
+S32 LLMeshRepoThread::sRequestWaterLevel = 0;
+
+// Base handler class for all mesh users of llcorehttp.
+// This is roughly equivalent to a Responder class in
+// traditional LL code.  The base is going to perform
+// common response/data handling in the inherited
+// onCompleted() method.  Derived classes, one for each
+// type of HTTP action, define processData() and
+// processFailure() methods to customize handling and
+// error messages.
+//
+// LLCore::HttpHandler
+//   LLMeshHandlerBase
+//     LLMeshHeaderHandler
+//     LLMeshLODHandler
+//     LLMeshSkinInfoHandler
+//     LLMeshDecompositionHandler
+//     LLMeshPhysicsShapeHandler
+//   LLMeshUploadThread
+
+class LLMeshHandlerBase : public LLCore::HttpHandler
 {
-	LOG_CLASS(LLMeshHeaderResponder);
 public:
-	LLVolumeParams mMeshParams;
-	bool mProcessed;
+	LOG_CLASS(LLMeshHandlerBase);
+	LLMeshHandlerBase()
+		: LLCore::HttpHandler(),
+		  mMeshParams(),
+		  mProcessed(false),
+		  mHttpHandle(LLCORE_HTTP_HANDLE_INVALID)
+		{}
 
-	LLMeshHeaderResponder(const LLVolumeParams& mesh_params)
-		: mMeshParams(mesh_params)
-	{
-		LLMeshRepoThread::incActiveHeaderRequests();
-		mProcessed = false;
-	}
+	virtual ~LLMeshHandlerBase()
+		{}
 
-	~LLMeshHeaderResponder()
-	{
-		if (!LLApp::isQuitting())
-		{
-			if (!mProcessed)
-			{ //something went wrong, retry
-				llwarns << "Timeout or service unavailable, retrying." << llendl;
-				LLMeshRepository::sHTTPRetryCount++;
-				LLMeshRepoThread::HeaderRequest req(mMeshParams);
-				LLMutexLock lock(gMeshRepo.mThread->mMutex);
-				gMeshRepo.mThread->mHeaderReqQ.push(req);
-			}
+protected:
+	LLMeshHandlerBase(const LLMeshHandlerBase &);				// Not defined
+	void operator=(const LLMeshHandlerBase &);					// Not defined
+	
+public:
+	virtual void onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response);
+	virtual void processData(LLCore::BufferArray * body, U8 * data, S32 data_size) = 0;
+	virtual void processFailure(LLCore::HttpStatus status) = 0;
+	
+public:
+	LLVolumeParams		mMeshParams;
+	bool				mProcessed;
+	LLCore::HttpHandle	mHttpHandle;
+};
 
-			LLMeshRepoThread::decActiveHeaderRequests();
-		}
-	}
 
-	virtual void completedRaw(const LLChannelDescriptors& channels,
-							  const LLIOPipe::buffer_ptr_t& buffer);
+// Subclass for header fetches.
+//
+// Thread:  repo
+class LLMeshHeaderHandler : public LLMeshHandlerBase
+{
+public:
+	LOG_CLASS(LLMeshHeaderHandler);
+	LLMeshHeaderHandler(const LLVolumeParams & mesh_params)
+		: LLMeshHandlerBase()
+	{
+		mMeshParams = mesh_params;
+		LLMeshRepoThread::incActiveHeaderRequests();
+	}
+	virtual ~LLMeshHeaderHandler();
 
+protected:
+	LLMeshHeaderHandler(const LLMeshHeaderHandler &);			// Not defined
+	void operator=(const LLMeshHeaderHandler &);				// Not defined
+	
+public:
+	virtual void processData(LLCore::BufferArray * body, U8 * data, S32 data_size);
+	virtual void processFailure(LLCore::HttpStatus status);
 };
 
-class LLMeshLODResponder : public LLCurl::Responder
+
+// Subclass for LOD fetches.
+//
+// Thread:  repo
+class LLMeshLODHandler : public LLMeshHandlerBase
 {
-	LOG_CLASS(LLMeshLODResponder);
 public:
-	LLVolumeParams mMeshParams;
-	S32 mLOD;
-	U32 mRequestedBytes;
-	U32 mOffset;
-	bool mProcessed;
-
-	LLMeshLODResponder(const LLVolumeParams& mesh_params, S32 lod, U32 offset, U32 requested_bytes)
-		: mMeshParams(mesh_params), mLOD(lod), mOffset(offset), mRequestedBytes(requested_bytes)
+	LLMeshLODHandler(const LLVolumeParams & mesh_params, S32 lod, U32 offset, U32 requested_bytes)
+		: LLMeshHandlerBase(),
+		  mLOD(lod),
+		  mRequestedBytes(requested_bytes),
+		  mOffset(offset)
 	{
+		mMeshParams = mesh_params;
 		LLMeshRepoThread::incActiveLODRequests();
-		mProcessed = false;
-	}
-
-	~LLMeshLODResponder()
-	{
-		if (!LLApp::isQuitting())
-		{
-			if (!mProcessed)
-			{
-				llwarns << "Killed without being processed, retrying." << llendl;
-				LLMeshRepository::sHTTPRetryCount++;
-				gMeshRepo.mThread->lockAndLoadMeshLOD(mMeshParams, mLOD);
-			}
-			LLMeshRepoThread::decActiveLODRequests();
-		}
 	}
+	virtual ~LLMeshLODHandler();
+	
+protected:
+	LLMeshLODHandler(const LLMeshLODHandler &);					// Not defined
+	void operator=(const LLMeshLODHandler &);					// Not defined
+	
+public:
+	virtual void processData(LLCore::BufferArray * body, U8 * data, S32 data_size);
+	virtual void processFailure(LLCore::HttpStatus status);
 
-	virtual void completedRaw(const LLChannelDescriptors& channels,
-							  const LLIOPipe::buffer_ptr_t& buffer);
-
-};
-
-class LLMeshSkinInfoResponder : public LLCurl::Responder
-{
-	LOG_CLASS(LLMeshSkinInfoResponder);
 public:
-	LLUUID mMeshID;
+	S32 mLOD;
 	U32 mRequestedBytes;
 	U32 mOffset;
-	bool mProcessed;
-
-	LLMeshSkinInfoResponder(const LLUUID& id, U32 offset, U32 size)
-		: mMeshID(id), mRequestedBytes(size), mOffset(offset)
-	{
-		mProcessed = false;
-	}
+};
 
-	~LLMeshSkinInfoResponder()
-	{
-		if (!LLApp::isQuitting() &&
-			!mProcessed &&
-			mMeshID.notNull())
-		{	// Something went wrong, retry
-			llwarns << "Timeout or service unavailable, retrying loadMeshSkinInfo() for " << mMeshID << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshSkinInfo(mMeshID);
-		}
-	}
 
-	virtual void completedRaw(const LLChannelDescriptors& channels,
-							  const LLIOPipe::buffer_ptr_t& buffer);
+// Subclass for skin info fetches.
+//
+// Thread:  repo
+class LLMeshSkinInfoHandler : public LLMeshHandlerBase
+{
+public:
+	LOG_CLASS(LLMeshSkinInfoHandler);
+	LLMeshSkinInfoHandler(const LLUUID& id, U32 offset, U32 size)
+		: LLMeshHandlerBase(),
+		  mMeshID(id),
+		  mRequestedBytes(size),
+		  mOffset(offset)
+	{}
+	virtual ~LLMeshSkinInfoHandler();
 
-};
+protected:
+	LLMeshSkinInfoHandler(const LLMeshSkinInfoHandler &);		// Not defined
+	void operator=(const LLMeshSkinInfoHandler &);				// Not defined
+	
+public:
+	virtual void processData(LLCore::BufferArray * body, U8 * data, S32 data_size);
+	virtual void processFailure(LLCore::HttpStatus status);
 
-class LLMeshDecompositionResponder : public LLCurl::Responder
-{
-	LOG_CLASS(LLMeshDecompositionResponder);
 public:
 	LLUUID mMeshID;
 	U32 mRequestedBytes;
 	U32 mOffset;
-	bool mProcessed;
-
-	LLMeshDecompositionResponder(const LLUUID& id, U32 offset, U32 size)
-		: mMeshID(id), mRequestedBytes(size), mOffset(offset)
-	{
-		mProcessed = false;
-	}
+};
 
-	~LLMeshDecompositionResponder()
-	{
-		if (!LLApp::isQuitting() &&
-			!mProcessed &&
-			mMeshID.notNull())
-		{	// Something went wrong, retry
-			llwarns << "Timeout or service unavailable, retrying loadMeshDecomposition() for " << mMeshID << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshDecomposition(mMeshID);
-		}
-	}
 
-	virtual void completedRaw(const LLChannelDescriptors& channels,
-							  const LLIOPipe::buffer_ptr_t& buffer);
+// Subclass for decomposition fetches.
+//
+// Thread:  repo
+class LLMeshDecompositionHandler : public LLMeshHandlerBase
+{
+public:
+	LOG_CLASS(LLMeshDecompositionHandler);
+	LLMeshDecompositionHandler(const LLUUID& id, U32 offset, U32 size)
+		: LLMeshHandlerBase(),
+		  mMeshID(id),
+		  mRequestedBytes(size),
+		  mOffset(offset)
+	{}
+	virtual ~LLMeshDecompositionHandler();
 
-};
+protected:
+	LLMeshDecompositionHandler(const LLMeshDecompositionHandler &);		// Not defined
+	void operator=(const LLMeshDecompositionHandler &);					// Not defined
+	
+public:
+	virtual void processData(LLCore::BufferArray * body, U8 * data, S32 data_size);
+	virtual void processFailure(LLCore::HttpStatus status);
 
-class LLMeshPhysicsShapeResponder : public LLCurl::Responder
-{
-	LOG_CLASS(LLMeshPhysicsShapeResponder);
 public:
 	LLUUID mMeshID;
 	U32 mRequestedBytes;
 	U32 mOffset;
-	bool mProcessed;
+};
 
-	LLMeshPhysicsShapeResponder(const LLUUID& id, U32 offset, U32 size)
-		: mMeshID(id), mRequestedBytes(size), mOffset(offset)
-	{
-		mProcessed = false;
-	}
 
-	~LLMeshPhysicsShapeResponder()
-	{
-		if (!LLApp::isQuitting() &&
-			!mProcessed &&
-			mMeshID.notNull())
-		{	// Something went wrong, retry
-			llwarns << "Timeout or service unavailable, retrying loadMeshPhysicsShape() for " << mMeshID << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshPhysicsShape(mMeshID);
-		}
-	}
+// Subclass for physics shape fetches.
+//
+// Thread:  repo
+class LLMeshPhysicsShapeHandler : public LLMeshHandlerBase
+{
+public:
+	LOG_CLASS(LLMeshPhysicsShapeHandler);
+	LLMeshPhysicsShapeHandler(const LLUUID& id, U32 offset, U32 size)
+		: LLMeshHandlerBase(),
+		  mMeshID(id),
+		  mRequestedBytes(size),
+		  mOffset(offset)
+	{}
+	virtual ~LLMeshPhysicsShapeHandler();
 
-	virtual void completedRaw(const LLChannelDescriptors& channels,
-							  const LLIOPipe::buffer_ptr_t& buffer);
+protected:
+	LLMeshPhysicsShapeHandler(const LLMeshPhysicsShapeHandler &);	// Not defined
+	void operator=(const LLMeshPhysicsShapeHandler &);				// Not defined
+	
+public:
+	virtual void processData(LLCore::BufferArray * body, U8 * data, S32 data_size);
+	virtual void processFailure(LLCore::HttpStatus status);
 
+public:
+	LLUUID		mMeshID;
+	U32			mRequestedBytes;
+	U32			mOffset;
 };
 
-void log_upload_error(S32 status, const LLSD& content, std::string stage, std::string model_name)
+
+void log_upload_error(LLCore::HttpStatus status, const LLSD& content,
+					  const char * const stage, const std::string & model_name)
 {
 	// Add notification popup.
 	LLSD args;
-	std::string message = content["error"]["message"];
-	std::string identifier = content["error"]["identifier"];
+	std::string message = content["error"]["message"].asString();
+	std::string identifier = content["error"]["identifier"].asString();
 	args["MESSAGE"] = message;
 	args["IDENTIFIER"] = identifier;
 	args["LABEL"] = model_name;
 	gMeshRepo.uploadError(args);
 
 	// Log details.
-	llwarns << "stage: " << stage << " http status: " << status << llendl;
+	LL_WARNS(LOG_MESH) << "Error in stage:  " << stage
+					   << ", Reason:  " << status.toString()
+					   << " (" << status.toTerseString() << ")" << LL_ENDL;
 	if (content.has("error"))
 	{
 		const LLSD& err = content["error"];
-		llwarns << "err: " << err << llendl;
-		llwarns << "mesh upload failed, stage '" << stage
-				<< "' error '" << err["error"].asString()
-				<< "', message '" << err["message"].asString()
-				<< "', id '" << err["identifier"].asString()
-				<< "'" << llendl;
+		LL_WARNS(LOG_MESH) << "error: " << err << LL_ENDL;
+		LL_WARNS(LOG_MESH) << "  mesh upload failed, stage '" << stage
+						   << "', error '" << err["error"].asString()
+						   << "', message '" << err["message"].asString()
+						   << "', id '" << err["identifier"].asString()
+						   << "'" << LL_ENDL;
 		if (err.has("errors"))
 		{
 			S32 error_num = 0;
@@ -400,13 +734,13 @@ void log_upload_error(S32 status, const LLSD& content, std::string stage, std::s
 				 ++it)
 			{
 				const LLSD& err_entry = *it;
-				llwarns << "error[" << error_num << "]:" << llendl;
+				LL_WARNS(LOG_MESH) << "  error[" << error_num << "]:" << LL_ENDL;
 				for (LLSD::map_const_iterator map_it = err_entry.beginMap();
 					 map_it != err_entry.endMap();
 					 ++map_it)
 				{
-					llwarns << "\t" << map_it->first << ": "
-							<< map_it->second << llendl;
+					LL_WARNS(LOG_MESH) << "    " << map_it->first << ":  "
+									   << map_it->second << LL_ENDL;
 				}
 				error_num++;
 			}
@@ -414,154 +748,71 @@ void log_upload_error(S32 status, const LLSD& content, std::string stage, std::s
 	}
 	else
 	{
-		llwarns << "bad mesh, no error information available" << llendl;
+		LL_WARNS(LOG_MESH) << "Bad response to mesh request, no additional error information available." << LL_ENDL;
 	}
 }
 
-class LLWholeModelFeeResponder: public LLCurl::Responder
+LLMeshRepoThread::LLMeshRepoThread()
+: LLThread("mesh repo"),
+  mHttpRequest(NULL),
+  mHttpOptions(NULL),
+  mHttpLargeOptions(NULL),
+  mHttpHeaders(NULL),
+  mHttpPolicyClass(LLCore::HttpRequest::DEFAULT_POLICY_ID),
+  mHttpLegacyPolicyClass(LLCore::HttpRequest::DEFAULT_POLICY_ID),
+  mHttpLargePolicyClass(LLCore::HttpRequest::DEFAULT_POLICY_ID),
+  mHttpPriority(0),
+  mGetMeshVersion(2)
+{ 
+	mMutex = new LLMutex(NULL);
+	mHeaderMutex = new LLMutex(NULL);
+	mSignal = new LLCondition(NULL);
+	mHttpRequest = new LLCore::HttpRequest;
+	mHttpOptions = new LLCore::HttpOptions;
+	mHttpOptions->setTransferTimeout(SMALL_MESH_XFER_TIMEOUT);
+	mHttpOptions->setUseRetryAfter(gSavedSettings.getBOOL("MeshUseHttpRetryAfter"));
+	mHttpLargeOptions = new LLCore::HttpOptions;
+	mHttpLargeOptions->setTransferTimeout(LARGE_MESH_XFER_TIMEOUT);
+	mHttpLargeOptions->setUseRetryAfter(gSavedSettings.getBOOL("MeshUseHttpRetryAfter"));
+	mHttpHeaders = new LLCore::HttpHeaders;
+	mHttpHeaders->append("Accept", "application/vnd.ll.mesh");
+	mHttpPolicyClass = LLAppViewer::instance()->getAppCoreHttp().getPolicy(LLAppCoreHttp::AP_MESH2);
+	mHttpLegacyPolicyClass = LLAppViewer::instance()->getAppCoreHttp().getPolicy(LLAppCoreHttp::AP_MESH1);
+	mHttpLargePolicyClass = LLAppViewer::instance()->getAppCoreHttp().getPolicy(LLAppCoreHttp::AP_LARGE_MESH);
+}
+
+
+LLMeshRepoThread::~LLMeshRepoThread()
 {
-	LOG_CLASS(LLWholeModelFeeResponder);
-	LLMeshUploadThread* mThread;
-	LLSD mModelData;
-	LLHandle<LLWholeModelFeeObserver> mObserverHandle;
-public:
-	LLWholeModelFeeResponder(LLMeshUploadThread* thread, LLSD& model_data, LLHandle<LLWholeModelFeeObserver> observer_handle):
-		mThread(thread),
-		mModelData(model_data),
-		mObserverHandle(observer_handle)
-	{
-		if (mThread)
-		{
-			mThread->startRequest();
-		}
-	}
+	LL_INFOS(LOG_MESH) << "Small GETs issued:  " << LLMeshRepository::sHTTPRequestCount
+					   << ", Large GETs issued:  " << LLMeshRepository::sHTTPLargeRequestCount
+					   << ", Max Lock Holdoffs:  " << LLMeshRepository::sMaxLockHoldoffs
+					   << LL_ENDL;
 
-	~LLWholeModelFeeResponder()
+	for (http_request_set::iterator iter(mHttpRequestSet.begin());
+		 iter != mHttpRequestSet.end();
+		 ++iter)
 	{
-		if (mThread)
-		{
-			mThread->stopRequest();
-		}
+		delete *iter;
 	}
-
-protected:
-	virtual void httpCompleted()
+	mHttpRequestSet.clear();
+	if (mHttpHeaders)
 	{
-		LLSD cc = getContent();
-		if (gSavedSettings.getS32("MeshUploadFakeErrors")&1)
-		{
-			cc = llsd_from_file("fake_upload_error.xml");
-		}
-
-		dump_llsd_to_file(cc,make_dump_name("whole_model_fee_response_",dump_num));
-
-		LLWholeModelFeeObserver* observer = mObserverHandle.get();
-
-		if (isGoodStatus() &&
-			cc["state"].asString() == "upload")
-		{
-			mThread->mWholeModelUploadURL = cc["uploader"].asString();
-
-			if (observer)
-			{
-				cc["data"]["upload_price"] = cc["upload_price"];
-				observer->onModelPhysicsFeeReceived(cc["data"], mThread->mWholeModelUploadURL);
-			}
-		}
-		else
-		{
-			llwarns << "fee request failed " << dumpResponse() << llendl;
-			S32 status = getStatus();
-			log_upload_error(status,cc,"fee",mModelData["name"]);
-			mThread->mWholeModelUploadURL = "";
-
-			if (observer)
-			{
-				observer->setModelPhysicsFeeErrorStatus(status, getReason());
-			}
-		}
+		mHttpHeaders->release();
+		mHttpHeaders = NULL;
 	}
-
-};
-
-class LLWholeModelUploadResponder: public LLCurl::Responder
-{
-	LOG_CLASS(LLWholeModelUploadResponder);
-	LLMeshUploadThread* mThread;
-	LLSD mModelData;
-	LLHandle<LLWholeModelUploadObserver> mObserverHandle;
-	
-public:
-	LLWholeModelUploadResponder(LLMeshUploadThread* thread, LLSD& model_data, LLHandle<LLWholeModelUploadObserver> observer_handle):
-		mThread(thread),
-		mModelData(model_data),
-		mObserverHandle(observer_handle)
+	if (mHttpOptions)
 	{
-		if (mThread)
-		{
-			mThread->startRequest();
-		}
+		mHttpOptions->release();
+		mHttpOptions = NULL;
 	}
-
-	~LLWholeModelUploadResponder()
+	if (mHttpLargeOptions)
 	{
-		if (mThread)
-		{
-			mThread->stopRequest();
-		}
-	}
-
-protected:
-	virtual void httpCompleted()
-	{
-		LLSD cc = getContent();
-		if (gSavedSettings.getS32("MeshUploadFakeErrors")&2)
-		{
-			cc = llsd_from_file("fake_upload_error.xml");
-		}
-
-		dump_llsd_to_file(cc,make_dump_name("whole_model_upload_response_",dump_num));
-		
-		LLWholeModelUploadObserver* observer = mObserverHandle.get();
-
-		// requested "mesh" asset type isn't actually the type
-		// of the resultant object, fix it up here.
-		if (isGoodStatus() &&
-			cc["state"].asString() == "complete")
-		{
-			mModelData["asset_type"] = "object";
-			gMeshRepo.updateInventory(LLMeshRepository::inventory_data(mModelData,cc));
-
-			if (observer)
-			{
-				doOnIdleOneTime(boost::bind(&LLWholeModelUploadObserver::onModelUploadSuccess, observer));
-			}
-		}
-		else
-		{
-			llwarns << "upload failed " << dumpResponse() << llendl;
-			std::string model_name = mModelData["name"].asString();
-			log_upload_error(getStatus(),cc,"upload",model_name);
-
-			if (observer)
-			{
-				doOnIdleOneTime(boost::bind(&LLWholeModelUploadObserver::onModelUploadFailure, observer));
-			}
-		}
+		mHttpLargeOptions->release();
+		mHttpLargeOptions = NULL;
 	}
-};
-
-LLMeshRepoThread::LLMeshRepoThread()
-: LLThread("mesh repo") 
-{ 
-	mWaiting = false;
-	mMutex = new LLMutex(NULL);
-	mHeaderMutex = new LLMutex(NULL);
-	mSignal = new LLCondition(NULL);
-}
-
-LLMeshRepoThread::~LLMeshRepoThread()
-{
+	delete mHttpRequest;
+	mHttpRequest = NULL;
 	delete mMutex;
 	mMutex = NULL;
 	delete mHeaderMutex;
@@ -572,109 +823,180 @@ LLMeshRepoThread::~LLMeshRepoThread()
 
 void LLMeshRepoThread::run()
 {
-	mCurlRequest = new LLCurlRequest();
 	LLCDResult res = LLConvexDecomposition::initThread();
 	if (res != LLCD_OK)
 	{
-		llwarns << "convex decomposition unable to be loaded" << llendl;
+		LL_WARNS(LOG_MESH) << "Convex decomposition unable to be loaded.  Expect severe problems." << LL_ENDL;
 	}
 
 	while (!LLApp::isQuitting())
 	{
-		mWaiting = true;
+		// *TODO:  Revise sleep/wake strategy and try to move away
+		// from polling operations in this thread.  We can sleep
+		// this thread hard when:
+		// * All Http requests are serviced
+		// * LOD request queue empty
+		// * Header request queue empty
+		// * Skin info request queue empty
+		// * Decomposition request queue empty
+		// * Physics shape request queue empty
+		// We wake the thread when any of the above become untrue.
+		// Will likely need a correctly-implemented condition variable to do this.
+		// On the other hand, this may actually be an effective and efficient scheme...
+		
 		mSignal->wait();
-		mWaiting = false;
 
-		if (!LLApp::isQuitting())
+		if (LLApp::isQuitting())
 		{
-			static U32 count = 0;
+			break;
+		}
+		
+		if (! mHttpRequestSet.empty())
+		{
+			// Dispatch all HttpHandler notifications
+			mHttpRequest->update(0L);
+		}
+		sRequestWaterLevel = mHttpRequestSet.size();			// Stats data update
+			
+		// NOTE: order of queue processing intentionally favors LOD requests over header requests
 
-			static F32 last_hundred = gFrameTimeSeconds;
+		while (!mLODReqQ.empty() && mHttpRequestSet.size() < sRequestHighWater)
+		{
+			if (! mMutex)
+			{
+				break;
+			}
+			mMutex->lock();
+			LODRequest req = mLODReqQ.front();
+			mLODReqQ.pop();
+			LLMeshRepository::sLODProcessing--;
+			mMutex->unlock();
+			if (!fetchMeshLOD(req.mMeshParams, req.mLOD))		// failed, resubmit
+			{
+				mMutex->lock();
+				mLODReqQ.push(req) ; 
+				++LLMeshRepository::sLODProcessing;
+				mMutex->unlock();
+			}
+		}
 
-			if (gFrameTimeSeconds - last_hundred > 1.f)
-			{ //a second has gone by, clear count
-				last_hundred = gFrameTimeSeconds;
-				count = 0;	
+		while (!mHeaderReqQ.empty() && mHttpRequestSet.size() < sRequestHighWater)
+		{
+			if (! mMutex)
+			{
+				break;
+			}
+			mMutex->lock();
+			HeaderRequest req = mHeaderReqQ.front();
+			mHeaderReqQ.pop();
+			mMutex->unlock();
+			if (!fetchMeshHeader(req.mMeshParams))//failed, resubmit
+			{
+				mMutex->lock();
+				mHeaderReqQ.push(req) ;
+				mMutex->unlock();
 			}
+		}
 
-			// NOTE: throttling intentionally favors LOD requests over header requests
-			
-			while (!mLODReqQ.empty() && count < MAX_MESH_REQUESTS_PER_SECOND && sActiveLODRequests < sMaxConcurrentRequests)
+		// For the final three request lists, similar goal to above but
+		// slightly different queue structures.  Stay off the mutex when
+		// performing long-duration actions.
+
+		if (mHttpRequestSet.size() < sRequestHighWater
+			&& (! mSkinRequests.empty()
+				|| ! mDecompositionRequests.empty()
+				|| ! mPhysicsShapeRequests.empty()))
+		{
+			// Something to do probably, lock and double-check.  We don't want
+			// to hold the lock long here.  That will stall main thread activities
+			// so we bounce it.
+
+			mMutex->lock();
+			if (! mSkinRequests.empty() && mHttpRequestSet.size() < sRequestHighWater)
 			{
-				if (mMutex)
+				std::set<LLUUID> incomplete;
+				std::set<LLUUID>::iterator iter(mSkinRequests.begin());
+				while (iter != mSkinRequests.end() && mHttpRequestSet.size() < sRequestHighWater)
 				{
-					mMutex->lock();
-					LODRequest req = mLODReqQ.front();
-					mLODReqQ.pop();
-					LLMeshRepository::sLODProcessing--;
+					LLUUID mesh_id = *iter;
+					mSkinRequests.erase(iter);
 					mMutex->unlock();
-					if (!fetchMeshLOD(req.mMeshParams, req.mLOD, count))//failed, resubmit
+
+					if (! fetchMeshSkinInfo(mesh_id))
 					{
-						mMutex->lock();
-						mLODReqQ.push(req); 
-						mMutex->unlock();
+						incomplete.insert(mesh_id);
 					}
+
+					mMutex->lock();
+					iter = mSkinRequests.begin();
 				}
-			}
 
-			while (!mHeaderReqQ.empty() && count < MAX_MESH_REQUESTS_PER_SECOND && sActiveHeaderRequests < sMaxConcurrentRequests)
-			{
-				if (mMutex)
+				if (! incomplete.empty())
 				{
-					mMutex->lock();
-					HeaderRequest req = mHeaderReqQ.front();
-					mHeaderReqQ.pop();
-					mMutex->unlock();
-					if (!fetchMeshHeader(req.mMeshParams, count))//failed, resubmit
-					{
-						mMutex->lock();
-						mHeaderReqQ.push(req) ;
-						mMutex->unlock();
-					}
+					mSkinRequests.insert(incomplete.begin(), incomplete.end());
 				}
 			}
 
-			{ //mSkinRequests is protected by mSignal
+			// holding lock, try next list
+			// *TODO:  For UI/debug-oriented lists, we might drop the fine-
+			// grained locking as there's a lowered expectation of smoothness
+			// in these cases.
+			if (! mDecompositionRequests.empty() && mHttpRequestSet.size() < sRequestHighWater)
+			{
 				std::set<LLUUID> incomplete;
-				for (std::set<LLUUID>::iterator iter = mSkinRequests.begin(); iter != mSkinRequests.end(); ++iter)
+				std::set<LLUUID>::iterator iter(mDecompositionRequests.begin());
+				while (iter != mDecompositionRequests.end() && mHttpRequestSet.size() < sRequestHighWater)
 				{
 					LLUUID mesh_id = *iter;
-					if (!fetchMeshSkinInfo(mesh_id))
+					mDecompositionRequests.erase(iter);
+					mMutex->unlock();
+					
+					if (! fetchMeshDecomposition(mesh_id))
 					{
 						incomplete.insert(mesh_id);
 					}
+
+					mMutex->lock();
+					iter = mDecompositionRequests.begin();
 				}
-				mSkinRequests = incomplete;
-			}
 
-			{ //mDecompositionRequests is protected by mSignal
-				std::set<LLUUID> incomplete;
-				for (std::set<LLUUID>::iterator iter = mDecompositionRequests.begin(); iter != mDecompositionRequests.end(); ++iter)
+				if (! incomplete.empty())
 				{
-					LLUUID mesh_id = *iter;
-					if (!fetchMeshDecomposition(mesh_id))
-					{
-						incomplete.insert(mesh_id);
-					}
+					mDecompositionRequests.insert(incomplete.begin(), incomplete.end());
 				}
-				mDecompositionRequests = incomplete;
 			}
 
-			{ //mPhysicsShapeRequests is protected by mSignal
+			// holding lock, final list
+			if (! mPhysicsShapeRequests.empty() && mHttpRequestSet.size() < sRequestHighWater)
+			{
 				std::set<LLUUID> incomplete;
-				for (std::set<LLUUID>::iterator iter = mPhysicsShapeRequests.begin(); iter != mPhysicsShapeRequests.end(); ++iter)
+				std::set<LLUUID>::iterator iter(mPhysicsShapeRequests.begin());
+				while (iter != mPhysicsShapeRequests.end() && mHttpRequestSet.size() < sRequestHighWater)
 				{
 					LLUUID mesh_id = *iter;
-					if (!fetchMeshPhysicsShape(mesh_id))
+					mPhysicsShapeRequests.erase(iter);
+					mMutex->unlock();
+					
+					if (! fetchMeshPhysicsShape(mesh_id))
 					{
 						incomplete.insert(mesh_id);
 					}
+
+					mMutex->lock();
+					iter = mPhysicsShapeRequests.begin();
 				}
-				mPhysicsShapeRequests = incomplete;
-			}
 
-			mCurlRequest->process();
+				if (! incomplete.empty())
+				{
+					mPhysicsShapeRequests.insert(incomplete.begin(), incomplete.end());
+				}
+			}
+			mMutex->unlock();
 		}
+
+		// For dev purposes only.  A dynamic change could make this false
+		// and that shouldn't assert.
+		// llassert_always(mHttpRequestSet.size() <= sRequestHighWater);
 	}
 	
 	if (mSignal->isLocked())
@@ -685,25 +1007,25 @@ void LLMeshRepoThread::run()
 	res = LLConvexDecomposition::quitThread();
 	if (res != LLCD_OK)
 	{
-		llwarns << "convex decomposition unable to be quit" << llendl;
+		LL_WARNS(LOG_MESH) << "Convex decomposition unable to be quit." << LL_ENDL;
 	}
-
-	delete mCurlRequest;
-	mCurlRequest = NULL;
 }
 
+// Mutex:  LLMeshRepoThread::mMutex must be held on entry
 void LLMeshRepoThread::loadMeshSkinInfo(const LLUUID& mesh_id)
-{ //protected by mSignal, no locking needed here
+{
 	mSkinRequests.insert(mesh_id);
 }
 
+// Mutex:  LLMeshRepoThread::mMutex must be held on entry
 void LLMeshRepoThread::loadMeshDecomposition(const LLUUID& mesh_id)
-{ //protected by mSignal, no locking needed here
+{
 	mDecompositionRequests.insert(mesh_id);
 }
 
+// Mutex:  LLMeshRepoThread::mMutex must be held on entry
 void LLMeshRepoThread::loadMeshPhysicsShape(const LLUUID& mesh_id)
-{ //protected by mSignal, no locking needed here
+{
 	mPhysicsShapeRequests.insert(mesh_id);
 }
 
@@ -716,7 +1038,6 @@ void LLMeshRepoThread::lockAndLoadMeshLOD(const LLVolumeParams& mesh_params, S32
 }
 
 
-
 void LLMeshRepoThread::loadMeshLOD(const LLVolumeParams& mesh_params, S32 lod)
 { //could be called from any thread
 	LLMutexLock lock(mMutex);
@@ -748,31 +1069,122 @@ void LLMeshRepoThread::loadMeshLOD(const LLVolumeParams& mesh_params, S32 lod)
 	}
 }
 
-//static 
-std::string LLMeshRepoThread::constructUrl(LLUUID mesh_id)
+// Mutex:  must be holding mMutex when called
+void LLMeshRepoThread::setGetMeshCaps(const std::string & get_mesh1,
+									  const std::string & get_mesh2,
+									  int pref_version)
 {
-	std::string http_url;
+	mGetMeshCapability = get_mesh1;
+	mGetMesh2Capability = get_mesh2;
+	mGetMeshVersion = pref_version;
+}
+
+
+// Constructs a Cap URL for the mesh.  Prefers a GetMesh2 cap
+// over a GetMesh cap.
+//
+// Mutex:  acquires mMutex
+void LLMeshRepoThread::constructUrl(LLUUID mesh_id, std::string * url, int * version)
+{
+	std::string res_url;
+	int res_version(2);
 	
 	if (gAgent.getRegion())
 	{
-		http_url = gMeshRepo.mGetMeshCapability; 
+		LLMutexLock lock(mMutex);
+
+		// Get a consistent pair of (cap string, version).  The
+		// locking could be eliminated here without loss of safety
+		// by using a set of staging values in setGetMeshCaps().
+		
+		if (! mGetMesh2Capability.empty() && mGetMeshVersion > 1)
+		{
+			res_url = mGetMesh2Capability;
+			res_version = 2;
+		}
+		else
+		{
+			res_url = mGetMeshCapability;
+			res_version = 1;
+		}
 	}
 
-	if (!http_url.empty())
+	if (! res_url.empty())
 	{
-		http_url += "/?mesh_id=";
-		http_url += mesh_id.asString().c_str();
+		res_url += "/?mesh_id=";
+		res_url += mesh_id.asString().c_str();
 	}
 	else
 	{
-		llwarns << "Current region does not have GetMesh capability!  Cannot load " << mesh_id << ".mesh" << llendl;
+		LL_WARNS_ONCE(LOG_MESH) << "Current region does not have GetMesh capability!  Cannot load "
+								<< mesh_id << ".mesh" << LL_ENDL;
 	}
 
-	return http_url;
+	*url = res_url;
+	*version = res_version;
 }
 
+// Issue an HTTP GET request with byte range using the right
+// policy class.  Large requests go to the large request class.
+// If the current region supports GetMesh2, we prefer that for
+// smaller requests otherwise we try to use the traditional
+// GetMesh capability and connection concurrency.
+//
+// @return		Valid handle or LLCORE_HTTP_HANDLE_INVALID.
+//				If the latter, actual status is found in
+//				mHttpStatus member which is valid until the
+//				next call to this method.
+//
+// Thread:  repo
+LLCore::HttpHandle LLMeshRepoThread::getByteRange(const std::string & url, int cap_version,
+												  size_t offset, size_t len,
+												  LLCore::HttpHandler * handler)
+{
+	LLCore::HttpHandle handle(LLCORE_HTTP_HANDLE_INVALID);
+	
+	if (len < LARGE_MESH_FETCH_THRESHOLD)
+	{
+		handle = mHttpRequest->requestGetByteRange((2 == cap_version
+													? mHttpPolicyClass
+													: mHttpLegacyPolicyClass),
+												   mHttpPriority,
+												   url,
+												   offset,
+												   len,
+												   mHttpOptions,
+												   mHttpHeaders,
+												   handler);
+		if (LLCORE_HTTP_HANDLE_INVALID != handle)
+		{
+			++LLMeshRepository::sHTTPRequestCount;
+		}
+	}
+	else
+	{
+		handle = mHttpRequest->requestGetByteRange(mHttpLargePolicyClass,
+												   mHttpPriority,
+												   url,
+												   offset,
+												   len,
+												   mHttpLargeOptions,
+												   mHttpHeaders,
+												   handler);
+		if (LLCORE_HTTP_HANDLE_INVALID != handle)
+		{
+			++LLMeshRepository::sHTTPLargeRequestCount;
+		}
+	}
+	if (LLCORE_HTTP_HANDLE_INVALID == handle)
+	{
+		// Something went wrong, capture the error code for caller.
+		mHttpStatus = mHttpRequest->getStatus();
+	}
+	return handle;
+}
+
+
 bool LLMeshRepoThread::fetchMeshSkinInfo(const LLUUID& mesh_id)
-{ //protected by mMutex
+{
 	
 	if (!mHeaderMutex)
 	{
@@ -787,7 +1199,8 @@ bool LLMeshRepoThread::fetchMeshSkinInfo(const LLUUID& mesh_id)
 		return false;
 	}
 
-	bool ret = true ;
+	++LLMeshRepository::sMeshRequestCount;
+	bool ret = true;
 	U32 header_size = mMeshHeaderSize[mesh_id];
 	
 	if (header_size > 0)
@@ -805,6 +1218,7 @@ bool LLMeshRepoThread::fetchMeshSkinInfo(const LLUUID& mesh_id)
 			if (file.getSize() >= offset+size)
 			{				
 				LLMeshRepository::sCacheBytesRead += size;
+				++LLMeshRepository::sCacheReads;
 				file.seek(offset);
 				U8* buffer = new U8[size];
 				file.read(buffer, size);
@@ -829,17 +1243,28 @@ bool LLMeshRepoThread::fetchMeshSkinInfo(const LLUUID& mesh_id)
 			}
 
 			//reading from VFS failed for whatever reason, fetch from sim
-			std::vector<std::string> headers;
-			headers.push_back(HTTP_OUT_HEADER_ACCEPT + ": " + HTTP_CONTENT_OCTET_STREAM);
+			int cap_version(2);
+			std::string http_url;
+			constructUrl(mesh_id, &http_url, &cap_version);
 
-			std::string http_url = constructUrl(mesh_id);
 			if (!http_url.empty())
-			{				
-				ret = mCurlRequest->getByteRange(http_url, headers, offset, size,
-												 new LLMeshSkinInfoResponder(mesh_id, offset, size));
-				if(ret)
+			{
+				LLMeshSkinInfoHandler * handler = new LLMeshSkinInfoHandler(mesh_id, offset, size);
+				LLCore::HttpHandle handle = getByteRange(http_url, cap_version, offset, size, handler);
+				if (LLCORE_HTTP_HANDLE_INVALID == handle)
+				{
+					LL_WARNS(LOG_MESH) << "HTTP GET request failed for skin info on mesh " << mID
+									   << ".  Reason:  " << mHttpStatus.toString()
+									   << " (" << mHttpStatus.toTerseString() << ")"
+									   << LL_ENDL;
+					delete handler;
+					ret = false;
+
+				}
+				else
 				{
-					LLMeshRepository::sHTTPRequestCount++;
+					handler->mHttpHandle = handle;
+					mHttpRequestSet.insert(handler);
 				}
 			}
 		}
@@ -854,7 +1279,7 @@ bool LLMeshRepoThread::fetchMeshSkinInfo(const LLUUID& mesh_id)
 }
 
 bool LLMeshRepoThread::fetchMeshDecomposition(const LLUUID& mesh_id)
-{ //protected by mMutex
+{
 	if (!mHeaderMutex)
 	{
 		return false;
@@ -868,8 +1293,9 @@ bool LLMeshRepoThread::fetchMeshDecomposition(const LLUUID& mesh_id)
 		return false;
 	}
 
+	++LLMeshRepository::sMeshRequestCount;
 	U32 header_size = mMeshHeaderSize[mesh_id];
-	bool ret = true ;
+	bool ret = true;
 	
 	if (header_size > 0)
 	{
@@ -886,6 +1312,7 @@ bool LLMeshRepoThread::fetchMeshDecomposition(const LLUUID& mesh_id)
 			if (file.getSize() >= offset+size)
 			{
 				LLMeshRepository::sCacheBytesRead += size;
+				++LLMeshRepository::sCacheReads;
 
 				file.seek(offset);
 				U8* buffer = new U8[size];
@@ -911,17 +1338,27 @@ bool LLMeshRepoThread::fetchMeshDecomposition(const LLUUID& mesh_id)
 			}
 
 			//reading from VFS failed for whatever reason, fetch from sim
-			std::vector<std::string> headers;
-			headers.push_back(HTTP_OUT_HEADER_ACCEPT + ": " + HTTP_CONTENT_OCTET_STREAM);
-
-			std::string http_url = constructUrl(mesh_id);
+			int cap_version(2);
+			std::string http_url;
+			constructUrl(mesh_id, &http_url, &cap_version);
+			
 			if (!http_url.empty())
-			{				
-				ret = mCurlRequest->getByteRange(http_url, headers, offset, size,
-												 new LLMeshDecompositionResponder(mesh_id, offset, size));
-				if(ret)
+			{
+				LLMeshDecompositionHandler * handler = new LLMeshDecompositionHandler(mesh_id, offset, size);
+				LLCore::HttpHandle handle = getByteRange(http_url, cap_version, offset, size, handler);
+				if (LLCORE_HTTP_HANDLE_INVALID == handle)
+				{
+					LL_WARNS(LOG_MESH) << "HTTP GET request failed for decomposition mesh " << mID
+									   << ".  Reason:  " << mHttpStatus.toString()
+									   << " (" << mHttpStatus.toTerseString() << ")"
+									   << LL_ENDL;
+					delete handler;
+					ret = false;
+				}
+				else
 				{
-					LLMeshRepository::sHTTPRequestCount++;
+					handler->mHttpHandle = handle;
+					mHttpRequestSet.insert(handler);
 				}
 			}
 		}
@@ -936,7 +1373,7 @@ bool LLMeshRepoThread::fetchMeshDecomposition(const LLUUID& mesh_id)
 }
 
 bool LLMeshRepoThread::fetchMeshPhysicsShape(const LLUUID& mesh_id)
-{ //protected by mMutex
+{
 	if (!mHeaderMutex)
 	{
 		return false;
@@ -950,8 +1387,9 @@ bool LLMeshRepoThread::fetchMeshPhysicsShape(const LLUUID& mesh_id)
 		return false;
 	}
 
+	++LLMeshRepository::sMeshRequestCount;
 	U32 header_size = mMeshHeaderSize[mesh_id];
-	bool ret = true ;
+	bool ret = true;
 
 	if (header_size > 0)
 	{
@@ -968,6 +1406,7 @@ bool LLMeshRepoThread::fetchMeshPhysicsShape(const LLUUID& mesh_id)
 			if (file.getSize() >= offset+size)
 			{
 				LLMeshRepository::sCacheBytesRead += size;
+				++LLMeshRepository::sCacheReads;
 				file.seek(offset);
 				U8* buffer = new U8[size];
 				file.read(buffer, size);
@@ -992,18 +1431,27 @@ bool LLMeshRepoThread::fetchMeshPhysicsShape(const LLUUID& mesh_id)
 			}
 
 			//reading from VFS failed for whatever reason, fetch from sim
-			std::vector<std::string> headers;
-			headers.push_back(HTTP_OUT_HEADER_ACCEPT + ": " + HTTP_CONTENT_OCTET_STREAM);
-
-			std::string http_url = constructUrl(mesh_id);
+			int cap_version(2);
+			std::string http_url;
+			constructUrl(mesh_id, &http_url, &cap_version);
+			
 			if (!http_url.empty())
-			{				
-				ret = mCurlRequest->getByteRange(http_url, headers, offset, size,
-												 new LLMeshPhysicsShapeResponder(mesh_id, offset, size));
-
-				if(ret)
+			{
+				LLMeshPhysicsShapeHandler * handler = new LLMeshPhysicsShapeHandler(mesh_id, offset, size);
+				LLCore::HttpHandle handle = getByteRange(http_url, cap_version, offset, size, handler);
+				if (LLCORE_HTTP_HANDLE_INVALID == handle)
+				{
+					LL_WARNS(LOG_MESH) << "HTTP GET request failed for physics shape on mesh " << mID
+									   << ".  Reason:  " << mHttpStatus.toString()
+									   << " (" << mHttpStatus.toTerseString() << ")"
+									   << LL_ENDL;
+					delete handler;
+					ret = false;
+				}
+				else
 				{
-					LLMeshRepository::sHTTPRequestCount++;
+					handler->mHttpHandle = handle;
+					mHttpRequestSet.insert(handler);
 				}
 			}
 		}
@@ -1050,8 +1498,10 @@ void LLMeshRepoThread::decActiveHeaderRequests()
 }
 
 //return false if failed to get header
-bool LLMeshRepoThread::fetchMeshHeader(const LLVolumeParams& mesh_params, U32& count)
+bool LLMeshRepoThread::fetchMeshHeader(const LLVolumeParams& mesh_params)
 {
+	++LLMeshRepository::sMeshRequestCount;
+
 	{
 		//look for mesh in asset in vfs
 		LLVFile file(gVFS, mesh_params.getSculptID(), LLAssetType::AT_MESH);
@@ -1059,43 +1509,57 @@ bool LLMeshRepoThread::fetchMeshHeader(const LLVolumeParams& mesh_params, U32& c
 		S32 size = file.getSize();
 
 		if (size > 0)
-		{ //NOTE -- if the header size is ever more than 4KB, this will break
-			U8 buffer[4096];
-			S32 bytes = llmin(size, 4096);
+		{
+			// *NOTE:  if the header size is ever more than 4KB, this will break
+			U8 buffer[MESH_HEADER_SIZE];
+			S32 bytes = llmin(size, MESH_HEADER_SIZE);
 			LLMeshRepository::sCacheBytesRead += bytes;	
+			++LLMeshRepository::sCacheReads;
 			file.read(buffer, bytes);
 			if (headerReceived(mesh_params, buffer, bytes))
-			{ //did not do an HTTP request, return false
+			{
+				// Found mesh in VFS cache
 				return true;
 			}
 		}
 	}
 
 	//either cache entry doesn't exist or is corrupt, request header from simulator	
-	bool retval = true ;
-	std::vector<std::string> headers;
-	headers.push_back(HTTP_OUT_HEADER_ACCEPT + ": " + HTTP_CONTENT_OCTET_STREAM);
-
-	std::string http_url = constructUrl(mesh_params.getSculptID());
+	bool retval = true;
+	int cap_version(2);
+	std::string http_url;
+	constructUrl(mesh_params.getSculptID(), &http_url, &cap_version);
+	
 	if (!http_url.empty())
 	{
 		//grab first 4KB if we're going to bother with a fetch.  Cache will prevent future fetches if a full mesh fits
 		//within the first 4KB
 		//NOTE -- this will break of headers ever exceed 4KB		
-		retval = mCurlRequest->getByteRange(http_url, headers, 0, 4096, new LLMeshHeaderResponder(mesh_params));
-		if(retval)
+
+		LLMeshHeaderHandler * handler = new LLMeshHeaderHandler(mesh_params);
+		LLCore::HttpHandle handle = getByteRange(http_url, cap_version, 0, MESH_HEADER_SIZE, handler);
+		if (LLCORE_HTTP_HANDLE_INVALID == handle)
+		{
+			LL_WARNS(LOG_MESH) << "HTTP GET request failed for mesh header " << mID
+							   << ".  Reason:  " << mHttpStatus.toString()
+							   << " (" << mHttpStatus.toTerseString() << ")"
+							   << LL_ENDL;
+			delete handler;
+			retval = false;
+		}
+		else
 		{
-			LLMeshRepository::sHTTPRequestCount++;
+			handler->mHttpHandle = handle;
+			mHttpRequestSet.insert(handler);
 		}
-		count++;
 	}
 
 	return retval;
 }
 
 //return false if failed to get mesh lod.
-bool LLMeshRepoThread::fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod, U32& count)
-{ //protected by mMutex
+bool LLMeshRepoThread::fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod)
+{
 	if (!mHeaderMutex)
 	{
 		return false;
@@ -1103,6 +1567,7 @@ bool LLMeshRepoThread::fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod,
 
 	mHeaderMutex->lock();
 
+	++LLMeshRepository::sMeshRequestCount;
 	bool retval = true;
 
 	LLUUID mesh_id = mesh_params.getSculptID();
@@ -1124,6 +1589,7 @@ bool LLMeshRepoThread::fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod,
 			if (file.getSize() >= offset+size)
 			{
 				LLMeshRepository::sCacheBytesRead += size;
+				++LLMeshRepository::sCacheReads;
 				file.seek(offset);
 				U8* buffer = new U8[size];
 				file.read(buffer, size);
@@ -1148,20 +1614,29 @@ bool LLMeshRepoThread::fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod,
 			}
 
 			//reading from VFS failed for whatever reason, fetch from sim
-			std::vector<std::string> headers;
-			headers.push_back(HTTP_OUT_HEADER_ACCEPT + ": " + HTTP_CONTENT_OCTET_STREAM);
-
-			std::string http_url = constructUrl(mesh_id);
+			int cap_version(2);
+			std::string http_url;
+			constructUrl(mesh_id, &http_url, &cap_version);
+			
 			if (!http_url.empty())
-			{				
-				retval = mCurlRequest->getByteRange(constructUrl(mesh_id), headers, offset, size,
-										   new LLMeshLODResponder(mesh_params, lod, offset, size));
-
-				if(retval)
+			{
+				LLMeshLODHandler * handler = new LLMeshLODHandler(mesh_params, lod, offset, size);
+				LLCore::HttpHandle handle = getByteRange(http_url, cap_version, offset, size, handler);
+				if (LLCORE_HTTP_HANDLE_INVALID == handle)
+				{
+					LL_WARNS(LOG_MESH) << "HTTP GET request failed for LOD on mesh " << mID
+									   << ".  Reason:  " << mHttpStatus.toString()
+									   << " (" << mHttpStatus.toTerseString() << ")"
+									   << LL_ENDL;
+					delete handler;
+					retval = false;
+				}
+				else
 				{
-					LLMeshRepository::sHTTPRequestCount++;
+					handler->mHttpHandle = handle;
+					mHttpRequestSet.insert(handler);
+					// *NOTE:  Allowing a re-request, not marking as unavailable.  Is that correct?
 				}
-				count++;
 			}
 			else
 			{
@@ -1183,6 +1658,7 @@ bool LLMeshRepoThread::fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod,
 
 bool LLMeshRepoThread::headerReceived(const LLVolumeParams& mesh_params, U8* data, S32 data_size)
 {
+	const LLUUID mesh_id = mesh_params.getSculptID();
 	LLSD header;
 	
 	U32 header_size = 0;
@@ -1203,7 +1679,8 @@ bool LLMeshRepoThread::headerReceived(const LLVolumeParams& mesh_params, U8* dat
 
 		if (!LLSDSerialize::fromBinary(header, stream, data_size))
 		{
-			llwarns << "Mesh header parse error.  Not a valid mesh asset!" << llendl;
+			LL_WARNS(LOG_MESH) << "Mesh header parse error.  Not a valid mesh asset!  ID:  " << mesh_id
+							   << LL_ENDL;
 			return false;
 		}
 
@@ -1211,13 +1688,12 @@ bool LLMeshRepoThread::headerReceived(const LLVolumeParams& mesh_params, U8* dat
 	}
 	else
 	{
-		llinfos
-			<< "Marking header as non-existent, will not retry." << llendl;
+		LL_INFOS(LOG_MESH) << "Non-positive data size.  Marking header as non-existent, will not retry.  ID:  " << mesh_id
+						   << LL_ENDL;
 		header["404"] = 1;
 	}
 
 	{
-		LLUUID mesh_id = mesh_params.getSculptID();
 		
 		{
 			LLMutexLock lock(mHeaderMutex);
@@ -1225,6 +1701,7 @@ bool LLMeshRepoThread::headerReceived(const LLVolumeParams& mesh_params, U8* dat
 			mMeshHeader[mesh_id] = header;
 		}
 
+		
 		LLMutexLock lock(mMutex); // make sure only one thread access mPendingLOD at the same time.
 
 		//check for pending requests
@@ -1278,7 +1755,8 @@ bool LLMeshRepoThread::skinInfoReceived(const LLUUID& mesh_id, U8* data, S32 dat
 
 		if (!unzip_llsd(skin, stream, data_size))
 		{
-			llwarns << "Mesh skin info parse error.  Not a valid mesh asset!" << llendl;
+			LL_WARNS(LOG_MESH) << "Mesh skin info parse error.  Not a valid mesh asset!  ID:  " << mesh_id
+							   << LL_ENDL;
 			return false;
 		}
 	}
@@ -1287,8 +1765,11 @@ bool LLMeshRepoThread::skinInfoReceived(const LLUUID& mesh_id, U8* data, S32 dat
 		LLMeshSkinInfo info(skin);
 		info.mMeshID = mesh_id;
 
-		//llinfos<<"info pelvis offset"<<info.mPelvisOffset<<llendl;
-		mSkinInfoQ.push(info);
+		// LL_DEBUGS(LOG_MESH) << "info pelvis offset" << info.mPelvisOffset << LL_ENDL;
+		{
+			LLMutexLock lock(mMutex);
+			mSkinInfoQ.push_back(info);
+		}
 	}
 
 	return true;
@@ -1306,7 +1787,8 @@ bool LLMeshRepoThread::decompositionReceived(const LLUUID& mesh_id, U8* data, S3
 
 		if (!unzip_llsd(decomp, stream, data_size))
 		{
-			llwarns << "Mesh decomposition parse error.  Not a valid mesh asset!" << llendl;
+			LL_WARNS(LOG_MESH) << "Mesh decomposition parse error.  Not a valid mesh asset!  ID:  " << mesh_id
+							   << LL_ENDL;
 			return false;
 		}
 	}
@@ -1314,7 +1796,10 @@ bool LLMeshRepoThread::decompositionReceived(const LLUUID& mesh_id, U8* data, S3
 	{
 		LLModel::Decomposition* d = new LLModel::Decomposition(decomp);
 		d->mMeshID = mesh_id;
-		mDecompositionQ.push(d);
+		{
+			LLMutexLock lock(mMutex);
+			mDecompositionQ.push_back(d);
+		}
 	}
 
 	return true;
@@ -1373,15 +1858,20 @@ bool LLMeshRepoThread::physicsShapeReceived(const LLUUID& mesh_id, U8* data, S32
 		}
 	}
 
-	mDecompositionQ.push(d);
+	{
+		LLMutexLock lock(mMutex);
+		mDecompositionQ.push_back(d);
+	}
 	return true;
 }
 
 LLMeshUploadThread::LLMeshUploadThread(LLMeshUploadThread::instance_list& data, LLVector3& scale, bool upload_textures,
-										bool upload_skin, bool upload_joints, std::string upload_url, bool do_upload,
-					   LLHandle<LLWholeModelFeeObserver> fee_observer, LLHandle<LLWholeModelUploadObserver> upload_observer)
-: LLThread("mesh upload"),
-	mDiscarded(FALSE),
+									   bool upload_skin, bool upload_joints, const std::string & upload_url, bool do_upload,
+									   LLHandle<LLWholeModelFeeObserver> fee_observer,
+									   LLHandle<LLWholeModelUploadObserver> upload_observer)
+  : LLThread("mesh upload"),
+	LLCore::HttpHandler(),
+	mDiscarded(false),
 	mDoUpload(do_upload),
 	mWholeModelUploadURL(upload_url),
 	mFeeObserverHandle(fee_observer),
@@ -1392,7 +1882,6 @@ LLMeshUploadThread::LLMeshUploadThread(LLMeshUploadThread::instance_list& data,
 	mUploadSkin = upload_skin;
 	mUploadJoints = upload_joints;
 	mMutex = new LLMutex(NULL);
-	mCurlRequest = NULL;
 	mPendingUploads = 0;
 	mFinished = false;
 	mOrigin = gAgent.getPositionAgent();
@@ -1402,12 +1891,33 @@ LLMeshUploadThread::LLMeshUploadThread(LLMeshUploadThread::instance_list& data,
 
 	mOrigin += gAgent.getAtAxis() * scale.magVec();
 
-	mMeshUploadTimeOut = gSavedSettings.getS32("MeshUploadTimeOut") ;
+	mMeshUploadTimeOut = gSavedSettings.getS32("MeshUploadTimeOut");
+
+	mHttpRequest = new LLCore::HttpRequest;
+	mHttpOptions = new LLCore::HttpOptions;
+	mHttpOptions->setTransferTimeout(mMeshUploadTimeOut);
+	mHttpOptions->setUseRetryAfter(gSavedSettings.getBOOL("MeshUseHttpRetryAfter"));
+	mHttpOptions->setRetries(UPLOAD_RETRY_LIMIT);
+	mHttpHeaders = new LLCore::HttpHeaders;
+	mHttpHeaders->append("Content-Type", "application/llsd+xml");
+	mHttpPolicyClass = LLAppViewer::instance()->getAppCoreHttp().getPolicy(LLAppCoreHttp::AP_UPLOADS);
+	mHttpPriority = 0;
 }
 
 LLMeshUploadThread::~LLMeshUploadThread()
 {
-
+	if (mHttpHeaders)
+	{
+		mHttpHeaders->release();
+		mHttpHeaders = NULL;
+	}
+	if (mHttpOptions)
+	{
+		mHttpOptions->release();
+		mHttpOptions = NULL;
+	}
+	delete mHttpRequest;
+	mHttpRequest = NULL;
 }
 
 LLMeshUploadThread::DecompRequest::DecompRequest(LLModel* mdl, LLModel* base_model, LLMeshUploadThread* thread)
@@ -1449,14 +1959,14 @@ void LLMeshUploadThread::preStart()
 
 void LLMeshUploadThread::discard()
 {
-	LLMutexLock lock(mMutex) ;
-	mDiscarded = TRUE ;
+	LLMutexLock lock(mMutex);
+	mDiscarded = true;
 }
 
-BOOL LLMeshUploadThread::isDiscarded()
+bool LLMeshUploadThread::isDiscarded() const
 {
-	LLMutexLock lock(mMutex) ;
-	return mDiscarded ;
+	LLMutexLock lock(mMutex);
+	return mDiscarded;
 }
 
 void LLMeshUploadThread::run()
@@ -1707,9 +2217,15 @@ void LLMeshUploadThread::generateHulls()
 		}
 	}
 		
-	if(has_valid_requests)
-	{
-		while (!mPhysicsComplete)
+	if (has_valid_requests)
+	{
+		// *NOTE:  Interesting livelock condition on shutdown.  If there
+		// is an upload request in generateHulls() when shutdown starts,
+		// the main thread isn't available to manage communication between
+		// the decomposition thread and the upload thread and this loop
+		// wouldn't complete in turn stalling the main thread.  The check
+		// on isDiscarded() prevents that.
+		while (! mPhysicsComplete && ! isDiscarded())
 		{
 			apr_sleep(100);
 		}
@@ -1718,86 +2234,266 @@ void LLMeshUploadThread::generateHulls()
 
 void LLMeshUploadThread::doWholeModelUpload()
 {
-	mCurlRequest = new LLCurlRequest();
+	LL_DEBUGS(LOG_MESH) << "Starting model upload.  Instances:  " << mInstance.size() << LL_ENDL;
 
 	if (mWholeModelUploadURL.empty())
 	{
-		llinfos << "unable to upload, fee request failed" << llendl;
+		LL_WARNS(LOG_MESH) << "Missing mesh upload capability, unable to upload, fee request failed."
+						   << LL_ENDL;
 	}
 	else
 	{
 		generateHulls();
-
-		LLSD full_model_data;
-		wholeModelToLLSD(full_model_data, true);
-		LLSD body = full_model_data["asset_resources"];
-		dump_llsd_to_file(body,make_dump_name("whole_model_body_",dump_num));
-		LLCurlRequest::headers_t headers;
-
+		LL_DEBUGS(LOG_MESH) << "Hull generation completed." << LL_ENDL;
+
+		mModelData = LLSD::emptyMap();
+		wholeModelToLLSD(mModelData, true);
+		LLSD body = mModelData["asset_resources"];
+		dump_llsd_to_file(body, make_dump_name("whole_model_body_", dump_num));
+
+		LLCore::BufferArray * ba = new LLCore::BufferArray;
+		LLCore::BufferArrayStream bas(ba);
+		LLSDSerialize::toXML(body, bas);
+		// LLSDSerialize::toXML(mModelData, bas);		// <- Enabling this will generate a convenient upload error
+		LLCore::HttpHandle handle = mHttpRequest->requestPost(mHttpPolicyClass,
+															  mHttpPriority,
+															  mWholeModelUploadURL,
+															  ba,
+															  mHttpOptions,
+															  mHttpHeaders,
+															  this);
+		ba->release();
+		
+		if (LLCORE_HTTP_HANDLE_INVALID == handle)
+		{
+			mHttpStatus = mHttpRequest->getStatus();
+		
+			LL_WARNS(LOG_MESH) << "Couldn't issue request for full model upload.  Reason:  " << mHttpStatus.toString()
+							   << " (" << mHttpStatus.toTerseString() << ")"
+							   << LL_ENDL;
+		}
+		else
 		{
-			LLCurl::ResponderPtr responder = new LLWholeModelUploadResponder(this, full_model_data, mUploadObserverHandle) ;
+			U32 sleep_time(10);
+		
+			LL_DEBUGS(LOG_MESH) << "POST request issued." << LL_ENDL;
+			
+			mHttpRequest->update(0);
+			while (! LLApp::isQuitting() && ! finished() && ! isDiscarded())
+			{
+				ms_sleep(sleep_time);
+				sleep_time = llmin(250U, sleep_time + sleep_time);
+				mHttpRequest->update(0);
+			}
 
-			while(!mCurlRequest->post(mWholeModelUploadURL, headers, body, responder, mMeshUploadTimeOut))
+			if (isDiscarded())
+			{
+				LL_DEBUGS(LOG_MESH) << "Mesh upload operation discarded." << LL_ENDL;
+			}
+			else
 			{
-				//sleep for 10ms to prevent eating a whole core
-				apr_sleep(10000);
+				LL_DEBUGS(LOG_MESH) << "Mesh upload operation completed." << LL_ENDL;
 			}
 		}
-
-		do
-		{
-			mCurlRequest->process();
-			//sleep for 10ms to prevent eating a whole core
-			apr_sleep(10000);
-		} while (!LLAppViewer::isQuitting() && mPendingUploads > 0);
 	}
-
-	delete mCurlRequest;
-	mCurlRequest = NULL;
-
-	// Currently a no-op.
-	mFinished = true;
 }
 
 void LLMeshUploadThread::requestWholeModelFee()
 {
 	dump_num++;
 
-	mCurlRequest = new LLCurlRequest();
-
 	generateHulls();
 
-	LLSD model_data;
-	wholeModelToLLSD(model_data,false);
-	dump_llsd_to_file(model_data,make_dump_name("whole_model_fee_request_",dump_num));
-
-	LLCurlRequest::headers_t headers;
+	mModelData = LLSD::emptyMap();
+	wholeModelToLLSD(mModelData, false);
+	dump_llsd_to_file(mModelData, make_dump_name("whole_model_fee_request_", dump_num));
 
+	LLCore::BufferArray * ba = new LLCore::BufferArray;
+	LLCore::BufferArrayStream bas(ba);
+	LLSDSerialize::toXML(mModelData, bas);
+		
+	LLCore::HttpHandle handle = mHttpRequest->requestPost(mHttpPolicyClass,
+														  mHttpPriority,
+														  mWholeModelFeeCapability,
+														  ba,
+														  mHttpOptions,
+														  mHttpHeaders,
+														  this);
+	ba->release();
+	if (LLCORE_HTTP_HANDLE_INVALID == handle)
+	{
+		mHttpStatus = mHttpRequest->getStatus();
+		
+		LL_WARNS(LOG_MESH) << "Couldn't issue request for model fee.  Reason:  " << mHttpStatus.toString()
+						   << " (" << mHttpStatus.toTerseString() << ")"
+						   << LL_ENDL;
+	}
+	else
 	{
-		LLCurl::ResponderPtr responder = new LLWholeModelFeeResponder(this,model_data, mFeeObserverHandle) ;
-		while(!mCurlRequest->post(mWholeModelFeeCapability, headers, model_data, responder, mMeshUploadTimeOut))
+		U32 sleep_time(10);
+		
+		mHttpRequest->update(0);
+		while (! LLApp::isQuitting() && ! finished() && ! isDiscarded())
 		{
-			//sleep for 10ms to prevent eating a whole core
-			apr_sleep(10000);
+			ms_sleep(sleep_time);
+			sleep_time = llmin(250U, sleep_time + sleep_time);
+			mHttpRequest->update(0);
+		}
+		if (isDiscarded())
+		{
+			LL_DEBUGS(LOG_MESH) << "Mesh fee query operation discarded." << LL_ENDL;
 		}
 	}
+}
 
-	do
-	{
-		mCurlRequest->process();
-		//sleep for 10ms to prevent eating a whole core
-		apr_sleep(10000);
-	} while (!LLApp::isQuitting() && mPendingUploads > 0);
 
-	delete mCurlRequest;
-	mCurlRequest = NULL;
+// Does completion duty for both fee queries and actual uploads.
+void LLMeshUploadThread::onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response)
+{
+	// QA/Devel:  0x2 to enable fake error import on upload, 0x1 on fee check
+	const S32 fake_error(gSavedSettings.getS32("MeshUploadFakeErrors") & (mDoUpload ? 0xa : 0x5));
+	LLCore::HttpStatus status(response->getStatus());
+	if (fake_error)
+	{
+		status = (fake_error & 0x0c) ? LLCore::HttpStatus(500) : LLCore::HttpStatus(200);
+	}
+	std::string reason(status.toString());
+	LLSD body;
 
-	// Currently a no-op.
 	mFinished = true;
+
+	if (mDoUpload)
+	{
+		// model upload case
+		LLWholeModelUploadObserver * observer(mUploadObserverHandle.get());
+
+		if (! status)
+		{
+			LL_WARNS(LOG_MESH) << "Upload failed.  Reason:  " << reason
+							   << " (" << status.toTerseString() << ")"
+							   << LL_ENDL;
+
+			// Build a fake body for the alert generator
+			body["error"] = LLSD::emptyMap();
+			body["error"]["message"] = reason;
+			body["error"]["identifier"] = "NetworkError";		// from asset-upload/upload_util.py
+			log_upload_error(status, body, "upload", mModelData["name"].asString());
+
+			if (observer)
+			{
+				doOnIdleOneTime(boost::bind(&LLWholeModelUploadObserver::onModelUploadFailure, observer));
+			}
+		}
+		else
+		{
+			if (fake_error & 0x2)
+			{
+				body = llsd_from_file("fake_upload_error.xml");
+			}
+			else
+			{
+				LLCore::BufferArray * ba(response->getBody());
+				if (ba && ba->size())
+				{
+					LLCore::BufferArrayStream bas(ba);
+					LLSDSerialize::fromXML(body, bas);
+				}
+			}
+			dump_llsd_to_file(body, make_dump_name("whole_model_upload_response_", dump_num));
+
+			if (body["state"].asString() == "complete")
+			{
+				// requested "mesh" asset type isn't actually the type
+				// of the resultant object, fix it up here.
+				mModelData["asset_type"] = "object";
+				gMeshRepo.updateInventory(LLMeshRepository::inventory_data(mModelData, body));
+
+				if (observer)
+				{
+					doOnIdleOneTime(boost::bind(&LLWholeModelUploadObserver::onModelUploadSuccess, observer));
+				}
+			}
+			else
+			{
+				LL_WARNS(LOG_MESH) << "Upload failed.  Not in expected 'complete' state." << LL_ENDL;
+				log_upload_error(status, body, "upload", mModelData["name"].asString());
+
+				if (observer)
+				{
+					doOnIdleOneTime(boost::bind(&LLWholeModelUploadObserver::onModelUploadFailure, observer));
+				}
+			}
+		}
+	}
+	else
+	{
+		// model fee case
+		LLWholeModelFeeObserver* observer(mFeeObserverHandle.get());
+		mWholeModelUploadURL.clear();
+		
+		if (! status)
+		{
+			LL_WARNS(LOG_MESH) << "Fee request failed.  Reason:  " << reason
+							   << " (" << status.toTerseString() << ")"
+							   << LL_ENDL;
+
+			// Build a fake body for the alert generator
+			body["error"] = LLSD::emptyMap();
+			body["error"]["message"] = reason;
+			body["error"]["identifier"] = "NetworkError";		// from asset-upload/upload_util.py
+			log_upload_error(status, body, "fee", mModelData["name"].asString());
+
+			if (observer)
+			{
+				observer->setModelPhysicsFeeErrorStatus(status.toULong(), reason);
+			}
+		}
+		else
+		{
+			if (fake_error & 0x1)
+			{
+				body = llsd_from_file("fake_upload_error.xml");
+			}
+			else
+			{
+				LLCore::BufferArray * ba(response->getBody());
+				if (ba && ba->size())
+				{
+					LLCore::BufferArrayStream bas(ba);
+					LLSDSerialize::fromXML(body, bas);
+				}
+			}
+			dump_llsd_to_file(body, make_dump_name("whole_model_fee_response_", dump_num));
+		
+			if (body["state"].asString() == "upload")
+			{
+				mWholeModelUploadURL = body["uploader"].asString();
+
+				if (observer)
+				{
+					body["data"]["upload_price"] = body["upload_price"];
+					observer->onModelPhysicsFeeReceived(body["data"], mWholeModelUploadURL);
+				}
+			}
+			else
+			{
+				LL_WARNS(LOG_MESH) << "Fee request failed.  Not in expected 'upload' state." << LL_ENDL;
+				log_upload_error(status, body, "fee", mModelData["name"].asString());
+
+				if (observer)
+				{
+					observer->setModelPhysicsFeeErrorStatus(status.toULong(), reason);
+				}
+			}
+		}
+	}
 }
 
+
 void LLMeshRepoThread::notifyLoadedMeshes()
 {
+	bool update_metrics(false);
+	
 	if (!mMutex)
 	{
 		return;
@@ -1806,10 +2502,16 @@ void LLMeshRepoThread::notifyLoadedMeshes()
 	while (!mLoadedQ.empty())
 	{
 		mMutex->lock();
+		if (mLoadedQ.empty())
+		{
+			mMutex->unlock();
+			break;
+		}
 		LoadedMesh mesh = mLoadedQ.front();
 		mLoadedQ.pop();
 		mMutex->unlock();
 		
+		update_metrics = true;
 		if (mesh.mVolume && mesh.mVolume->getNumVolumeFaces() > 0)
 		{
 			gMeshRepo.notifyMeshLoaded(mesh.mMeshParams, mesh.mVolume);
@@ -1824,24 +2526,59 @@ void LLMeshRepoThread::notifyLoadedMeshes()
 	while (!mUnavailableQ.empty())
 	{
 		mMutex->lock();
+		if (mUnavailableQ.empty())
+		{
+			mMutex->unlock();
+			break;
+		}
+		
 		LODRequest req = mUnavailableQ.front();
 		mUnavailableQ.pop();
 		mMutex->unlock();
-		
+
+		update_metrics = true;
 		gMeshRepo.notifyMeshUnavailable(req.mMeshParams, req.mLOD);
 	}
 
-	while (!mSkinInfoQ.empty())
+	if (! mSkinInfoQ.empty() || ! mDecompositionQ.empty())
 	{
-		gMeshRepo.notifySkinInfoReceived(mSkinInfoQ.front());
-		mSkinInfoQ.pop();
+		if (mMutex->trylock())
+		{
+			std::list<LLMeshSkinInfo> skin_info_q;
+			std::list<LLModel::Decomposition*> decomp_q;
+
+			if (! mSkinInfoQ.empty())
+			{
+				skin_info_q.swap(mSkinInfoQ);
+			}
+			if (! mDecompositionQ.empty())
+			{
+				decomp_q.swap(mDecompositionQ);
+			}
+
+			mMutex->unlock();
+
+			// Process the elements free of the lock
+			while (! skin_info_q.empty())
+			{
+				gMeshRepo.notifySkinInfoReceived(skin_info_q.front());
+				skin_info_q.pop_front();
+			}
+
+			while (! decomp_q.empty())
+			{
+				gMeshRepo.notifyDecompositionReceived(decomp_q.front());
+				decomp_q.pop_front();
+			}
+		}
 	}
 
-	while (!mDecompositionQ.empty())
+	if (update_metrics)
 	{
-		gMeshRepo.notifyDecompositionReceived(mDecompositionQ.front());
-		mDecompositionQ.pop();
+		// Ping time-to-load metrics for mesh download operations.
+		LLMeshRepository::metricsProgress(0);
 	}
+	
 }
 
 S32 LLMeshRepoThread::getActualMeshLOD(const LLVolumeParams& mesh_params, S32 lod) 
@@ -1920,249 +2657,250 @@ void LLMeshRepository::cacheOutgoingMesh(LLMeshUploadData& data, LLSD& header)
 
 }
 
-void LLMeshLODResponder::completedRaw(const LLChannelDescriptors& channels,
-									  const LLIOPipe::buffer_ptr_t& buffer)
+void LLMeshHandlerBase::onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response)
 {
-	S32 status = getStatus();
 	mProcessed = true;
-	
-	// thread could have already be destroyed during logout
-	if( !gMeshRepo.mThread )
-	{
-		return;
-	}
-	
-	S32 data_size = buffer->countAfter(channels.in(), NULL);
 
-	// *TODO: What about 3xx redirect codes? What about status 400 (Bad Request)?
-	if (status < 200 || status > 400)
+	unsigned int retries(0U);
+	response->getRetries(NULL, &retries);
+	LLMeshRepository::sHTTPRetryCount += retries;
+
+	LLCore::HttpStatus status(response->getStatus());
+	if (! status || MESH_HTTP_RESPONSE_FAILED)
 	{
-		llwarns << dumpResponse() << llendl;
+		processFailure(status);
+		++LLMeshRepository::sHTTPErrorCount;
 	}
-
-	if (data_size < mRequestedBytes)
+	else
 	{
-		if (status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE)
-		{ //timeout or service unavailable, try again
-			llwarns << "Timeout or service unavailable, retrying." << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshLOD(mMeshParams, mLOD);
-		}
-		else
+		// From texture fetch code and may apply here:
+		//
+		// A warning about partial (HTTP 206) data.  Some grid services
+		// do *not* return a 'Content-Range' header in the response to
+		// Range requests with a 206 status.  We're forced to assume
+		// we get what we asked for in these cases until we can fix
+		// the services.
+		//
+		// May also need to deal with 200 status (full asset returned
+		// rather than partial) and 416 (request completely unsatisfyable).
+		// Always been exposed to these but are less likely here where
+		// speculative loads aren't done.
+		static const LLCore::HttpStatus par_status(HTTP_PARTIAL_CONTENT);
+
+		if (par_status != status)
 		{
-			llwarns << "Unhandled status " << dumpResponse() << llendl;
-			llassert(status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE); //intentionally trigger a breakpoint
+			LL_WARNS_ONCE(LOG_MESH) << "Non-206 successful status received for fetch:  "
+									<< status.toTerseString() << LL_ENDL;
 		}
-		return;
-	}
+		
+		LLCore::BufferArray * body(response->getBody());
+		S32 data_size(body ? body->size() : 0);
+		U8 * data(NULL);
 
-	LLMeshRepository::sBytesReceived += mRequestedBytes;
+		if (data_size > 0)
+		{
+			// *TODO: Try to get rid of data copying and add interfaces
+			// that support BufferArray directly.  Introduce a two-phase
+			// handler, optional first that takes a body, fallback second
+			// that requires a temporary allocation and data copy.
+			data = new U8[data_size];
+			body->read(0, (char *) data, data_size);
+			LLMeshRepository::sBytesReceived += data_size;
+		}
 
-	U8* data = NULL;
+		processData(body, data, data_size);
 
-	if (data_size > 0)
-	{
-		data = new U8[data_size];
-		buffer->readAfter(channels.in(), NULL, data, data_size);
+		delete [] data;
 	}
 
-	if (gMeshRepo.mThread->lodReceived(mMeshParams, mLOD, data, data_size))
-	{
-		//good fetch from sim, write to VFS for caching
-		LLVFile file(gVFS, mMeshParams.getSculptID(), LLAssetType::AT_MESH, LLVFile::WRITE);
+	// Release handler
+	gMeshRepo.mThread->mHttpRequestSet.erase(this);
+	delete this;		// Must be last statement
+}
 
-		S32 offset = mOffset;
-		S32 size = mRequestedBytes;
 
-		if (file.getSize() >= offset+size)
+LLMeshHeaderHandler::~LLMeshHeaderHandler()
+{
+	if (!LLApp::isQuitting())
+	{
+		if (! mProcessed)
 		{
-			file.seek(offset);
-			file.write(data, size);
-			LLMeshRepository::sCacheBytesWritten += size;
+			// something went wrong, retry
+			LL_WARNS(LOG_MESH) << "Mesh header fetch canceled unexpectedly, retrying." << LL_ENDL;
+			LLMeshRepoThread::HeaderRequest req(mMeshParams);
+			LLMutexLock lock(gMeshRepo.mThread->mMutex);
+			gMeshRepo.mThread->mHeaderReqQ.push(req);
 		}
+		LLMeshRepoThread::decActiveHeaderRequests();
 	}
-
-	delete [] data;
 }
 
-void LLMeshSkinInfoResponder::completedRaw(const LLChannelDescriptors& channels,
-										   const LLIOPipe::buffer_ptr_t& buffer)
+void LLMeshHeaderHandler::processFailure(LLCore::HttpStatus status)
 {
-	S32 status = getStatus();
-	mProcessed = true;
+	LL_WARNS(LOG_MESH) << "Error during mesh header handling.  ID:  " << mMeshParams.getSculptID()
+					   << ", Reason:  " << status.toString()
+					   << " (" << status.toTerseString() << ").  Not retrying."
+					   << LL_ENDL;
 
-	// thread could have already be destroyed during logout
-	if( !gMeshRepo.mThread )
+	// Can't get the header so none of the LODs will be available
+	LLMutexLock lock(gMeshRepo.mThread->mMutex);
+	for (int i(0); i < 4; ++i)
 	{
-		return;
+		gMeshRepo.mThread->mUnavailableQ.push(LLMeshRepoThread::LODRequest(mMeshParams, i));
 	}
+}
 
-	S32 data_size = buffer->countAfter(channels.in(), NULL);
-
-	// *TODO: What about 3xx redirect codes? What about status 400 (Bad Request)?
-	if (status < 200 || status > 400)
+void LLMeshHeaderHandler::processData(LLCore::BufferArray * body, U8 * data, S32 data_size)
+{
+	LLUUID mesh_id = mMeshParams.getSculptID();
+	bool success = (! MESH_HEADER_PROCESS_FAILED) && gMeshRepo.mThread->headerReceived(mMeshParams, data, data_size);
+	llassert(success);
+	if (! success)
 	{
-		llwarns << dumpResponse() << llendl;
-	}
+		// *TODO:  Get real reason for parse failure here.  Might we want to retry?
+		LL_WARNS(LOG_MESH) << "Unable to parse mesh header.  ID:  " << mesh_id
+						   << ", Unknown reason.  Not retrying."
+						   << LL_ENDL;
 
-	if (data_size < mRequestedBytes)
-	{
-		if (status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE)
-		{ //timeout or service unavailable, try again
-			llwarns << "Timeout or service unavailable, retrying loadMeshSkinInfo() for " << mMeshID << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshSkinInfo(mMeshID);
-		}
-		else
+		// Can't get the header so none of the LODs will be available
+		LLMutexLock lock(gMeshRepo.mThread->mMutex);
+		for (int i(0); i < 4; ++i)
 		{
-			llwarns << "Unhandled status " << dumpResponse() << llendl;
-			llassert(status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE); //intentionally trigger a breakpoint
+			gMeshRepo.mThread->mUnavailableQ.push(LLMeshRepoThread::LODRequest(mMeshParams, i));
 		}
-		return;
 	}
+	else if (data && data_size > 0)
+	{
+		// header was successfully retrieved from sim, cache in vfs
+		LLSD header = gMeshRepo.mThread->mMeshHeader[mesh_id];
 
-	LLMeshRepository::sBytesReceived += mRequestedBytes;
+		S32 version = header["version"].asInteger();
 
-	U8* data = NULL;
+		if (version <= MAX_MESH_VERSION)
+		{
+			std::stringstream str;
 
-	if (data_size > 0)
-	{
-		data = new U8[data_size];
-		buffer->readAfter(channels.in(), NULL, data, data_size);
-	}
+			S32 lod_bytes = 0;
 
-	if (gMeshRepo.mThread->skinInfoReceived(mMeshID, data, data_size))
-	{
-		//good fetch from sim, write to VFS for caching
-		LLVFile file(gVFS, mMeshID, LLAssetType::AT_MESH, LLVFile::WRITE);
+			for (U32 i = 0; i < LLModel::LOD_PHYSICS; ++i)
+			{
+				// figure out how many bytes we'll need to reserve in the file
+				const std::string & lod_name = header_lod[i];
+				lod_bytes = llmax(lod_bytes, header[lod_name]["offset"].asInteger()+header[lod_name]["size"].asInteger());
+			}
+		
+			// just in case skin info or decomposition is at the end of the file (which it shouldn't be)
+			lod_bytes = llmax(lod_bytes, header["skin"]["offset"].asInteger() + header["skin"]["size"].asInteger());
+			lod_bytes = llmax(lod_bytes, header["physics_convex"]["offset"].asInteger() + header["physics_convex"]["size"].asInteger());
 
-		S32 offset = mOffset;
-		S32 size = mRequestedBytes;
+			S32 header_bytes = (S32) gMeshRepo.mThread->mMeshHeaderSize[mesh_id];
+			S32 bytes = lod_bytes + header_bytes; 
 
-		if (file.getSize() >= offset+size)
-		{
-			LLMeshRepository::sCacheBytesWritten += size;
-			file.seek(offset);
-			file.write(data, size);
-		}
-	}
+		
+			// It's possible for the remote asset to have more data than is needed for the local cache
+			// only allocate as much space in the VFS as is needed for the local cache
+			data_size = llmin(data_size, bytes);
 
-	delete [] data;
-}
+			LLVFile file(gVFS, mesh_id, LLAssetType::AT_MESH, LLVFile::WRITE);
+			if (file.getMaxSize() >= bytes || file.setMaxSize(bytes))
+			{
+				LLMeshRepository::sCacheBytesWritten += data_size;
+				++LLMeshRepository::sCacheWrites;
 
-void LLMeshDecompositionResponder::completedRaw(const LLChannelDescriptors& channels,
-												const LLIOPipe::buffer_ptr_t& buffer)
-{
-	S32 status = getStatus();
-	mProcessed = true;
-	
-	if( !gMeshRepo.mThread )
-	{
-		return;
-	}
+				file.write(data, data_size);
+			
+				// zero out the rest of the file 
+				U8 block[MESH_HEADER_SIZE];
+				memset(block, 0, sizeof(block));
 
-	S32 data_size = buffer->countAfter(channels.in(), NULL);
+				while (bytes-file.tell() > sizeof(block))
+				{
+					file.write(block, sizeof(block));
+				}
 
-	// *TODO: What about 3xx redirect codes? What about status 400 (Bad Request)?
-	if (status < 200 || status > 400)
-	{
-		llwarns << dumpResponse() << llendl;
+				S32 remaining = bytes-file.tell();
+				if (remaining > 0)
+				{
+					file.write(block, remaining);
+				}
+			}
+		}
 	}
+}
 
-	if (data_size < mRequestedBytes)
+LLMeshLODHandler::~LLMeshLODHandler()
+{
+	if (! LLApp::isQuitting())
 	{
-		if (status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE)
-		{ //timeout or service unavailable, try again
-			llwarns << "Timeout or service unavailable, retrying loadMeshDecomposition() for " << mMeshID << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshDecomposition(mMeshID);
-		}
-		else
+		if (! mProcessed)
 		{
-			llwarns << "Unhandled status " << dumpResponse() << llendl;
-			llassert(status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE); //intentionally trigger a breakpoint
+			LL_WARNS(LOG_MESH) << "Mesh LOD fetch canceled unexpectedly, retrying." << LL_ENDL;
+			gMeshRepo.mThread->lockAndLoadMeshLOD(mMeshParams, mLOD);
 		}
-		return;
+		LLMeshRepoThread::decActiveLODRequests();
 	}
+}
 
-	LLMeshRepository::sBytesReceived += mRequestedBytes;
-
-	U8* data = NULL;
+void LLMeshLODHandler::processFailure(LLCore::HttpStatus status)
+{
+	LL_WARNS(LOG_MESH) << "Error during mesh LOD handling.  ID:  " << mMeshParams.getSculptID()
+					   << ", Reason:  " << status.toString()
+					   << " (" << status.toTerseString() << ").  Not retrying."
+					   << LL_ENDL;
 
-	if (data_size > 0)
-	{
-		data = new U8[data_size];
-		buffer->readAfter(channels.in(), NULL, data, data_size);
-	}
+	LLMutexLock lock(gMeshRepo.mThread->mMutex);
+	gMeshRepo.mThread->mUnavailableQ.push(LLMeshRepoThread::LODRequest(mMeshParams, mLOD));
+}
 
-	if (gMeshRepo.mThread->decompositionReceived(mMeshID, data, data_size))
+void LLMeshLODHandler::processData(LLCore::BufferArray * body, U8 * data, S32 data_size)
+{
+	if ((! MESH_LOD_PROCESS_FAILED) && gMeshRepo.mThread->lodReceived(mMeshParams, mLOD, data, data_size))
 	{
-		//good fetch from sim, write to VFS for caching
-		LLVFile file(gVFS, mMeshID, LLAssetType::AT_MESH, LLVFile::WRITE);
+		// good fetch from sim, write to VFS for caching
+		LLVFile file(gVFS, mMeshParams.getSculptID(), LLAssetType::AT_MESH, LLVFile::WRITE);
 
 		S32 offset = mOffset;
 		S32 size = mRequestedBytes;
 
 		if (file.getSize() >= offset+size)
 		{
-			LLMeshRepository::sCacheBytesWritten += size;
 			file.seek(offset);
 			file.write(data, size);
+			LLMeshRepository::sCacheBytesWritten += size;
+			++LLMeshRepository::sCacheWrites;
 		}
 	}
-
-	delete [] data;
-}
-
-void LLMeshPhysicsShapeResponder::completedRaw(const LLChannelDescriptors& channels,
-											   const LLIOPipe::buffer_ptr_t& buffer)
-{
-	S32 status = getStatus();
-	mProcessed = true;
-
-	// thread could have already be destroyed during logout
-	if( !gMeshRepo.mThread )
-	{
-		return;
-	}
-
-	S32 data_size = buffer->countAfter(channels.in(), NULL);
-
-	// *TODO: What about 3xx redirect codes? What about status 400 (Bad Request)?
-	if (status < 200 || status > 400)
-	{
-		llwarns << dumpResponse() << llendl;
-	}
-
-	if (data_size < mRequestedBytes)
+	else
 	{
-		if (status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE)
-		{ //timeout or service unavailable, try again
-			llwarns << "Timeout or service unavailable, retrying loadMeshPhysicsShape() for " << mMeshID << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			gMeshRepo.mThread->loadMeshPhysicsShape(mMeshID);
-		}
-		else
-		{
-			llwarns << "Unhandled status " << dumpResponse() << llendl;
-			llassert(status == HTTP_INTERNAL_ERROR || status == HTTP_SERVICE_UNAVAILABLE); //intentionally trigger a breakpoint
-		}
-		return;
+		LL_WARNS(LOG_MESH) << "Error during mesh LOD processing.  ID:  " << mMeshParams.getSculptID()
+						   << ", Unknown reason.  Not retrying."
+						   << LL_ENDL;
+		LLMutexLock lock(gMeshRepo.mThread->mMutex);
+		gMeshRepo.mThread->mUnavailableQ.push(LLMeshRepoThread::LODRequest(mMeshParams, mLOD));
 	}
+}
 
-	LLMeshRepository::sBytesReceived += mRequestedBytes;
+LLMeshSkinInfoHandler::~LLMeshSkinInfoHandler()
+{
+		llassert(mProcessed);
+}
 
-	U8* data = NULL;
+void LLMeshSkinInfoHandler::processFailure(LLCore::HttpStatus status)
+{
+	LL_WARNS(LOG_MESH) << "Error during mesh skin info handling.  ID:  " << mMeshID
+					   << ", Reason:  " << status.toString()
+					   << " (" << status.toTerseString() << ").  Not retrying."
+					   << LL_ENDL;
 
-	if (data_size > 0)
-	{
-		data = new U8[data_size];
-		buffer->readAfter(channels.in(), NULL, data, data_size);
-	}
+	// *TODO:  Mark mesh unavailable on error.  For now, simply leave
+	// request unfulfilled rather than retry forever.
+}
 
-	if (gMeshRepo.mThread->physicsShapeReceived(mMeshID, data, data_size))
+void LLMeshSkinInfoHandler::processData(LLCore::BufferArray * body, U8 * data, S32 data_size)
+{
+	if ((! MESH_SKIN_INFO_PROCESS_FAILED) && gMeshRepo.mThread->skinInfoReceived(mMeshID, data, data_size))
 	{
-		//good fetch from sim, write to VFS for caching
+		// good fetch from sim, write to VFS for caching
 		LLVFile file(gVFS, mMeshID, LLAssetType::AT_MESH, LLVFile::WRITE);
 
 		S32 offset = mOffset;
@@ -2171,142 +2909,108 @@ void LLMeshPhysicsShapeResponder::completedRaw(const LLChannelDescriptors& chann
 		if (file.getSize() >= offset+size)
 		{
 			LLMeshRepository::sCacheBytesWritten += size;
+			++LLMeshRepository::sCacheWrites;
 			file.seek(offset);
 			file.write(data, size);
 		}
 	}
-
-	delete [] data;
+	else
+	{
+		LL_WARNS(LOG_MESH) << "Error during mesh skin info processing.  ID:  " << mMeshID
+						   << ", Unknown reason.  Not retrying."
+						   << LL_ENDL;
+		// *TODO:  Mark mesh unavailable on error
+	}
 }
 
-void LLMeshHeaderResponder::completedRaw(const LLChannelDescriptors& channels,
-										 const LLIOPipe::buffer_ptr_t& buffer)
+LLMeshDecompositionHandler::~LLMeshDecompositionHandler()
 {
-	S32 status = getStatus();
-	mProcessed = true;
+		llassert(mProcessed);
+}
 
-	// thread could have already be destroyed during logout
-	if( !gMeshRepo.mThread )
-	{
-		return;
-	}
+void LLMeshDecompositionHandler::processFailure(LLCore::HttpStatus status)
+{
+	LL_WARNS(LOG_MESH) << "Error during mesh decomposition handling.  ID:  " << mMeshID
+					   << ", Reason:  " << status.toString()
+					   << " (" << status.toTerseString() << ").  Not retrying."
+					   << LL_ENDL;
+	// *TODO:  Mark mesh unavailable on error.  For now, simply leave
+	// request unfulfilled rather than retry forever.
+}
 
-	// *TODO: What about 3xx redirect codes? What about status 400 (Bad Request)?
-	if (status < 200 || status > 400)
+void LLMeshDecompositionHandler::processData(LLCore::BufferArray * body, U8 * data, S32 data_size)
+{
+	if ((! MESH_DECOMP_PROCESS_FAILED) && gMeshRepo.mThread->decompositionReceived(mMeshID, data, data_size))
 	{
-		//llwarns
-		//	<< "Header responder failed with status: "
-		//	<< status << ": " << reason << llendl;
-
-		// 503 (service unavailable) or 499 (internal Linden-generated error)
-		// can be due to server load and can be retried
-
-		// TODO*: Add maximum retry logic, exponential backoff
-		// and (somewhat more optional than the others) retries
-		// again after some set period of time
+		// good fetch from sim, write to VFS for caching
+		LLVFile file(gVFS, mMeshID, LLAssetType::AT_MESH, LLVFile::WRITE);
 
-		if (status == HTTP_SERVICE_UNAVAILABLE || status == HTTP_REQUEST_TIME_OUT || status == HTTP_INTERNAL_ERROR)
-		{ //retry
-			llwarns << "Timeout or service unavailable, retrying." << llendl;
-			LLMeshRepository::sHTTPRetryCount++;
-			LLMeshRepoThread::HeaderRequest req(mMeshParams);
-			LLMutexLock lock(gMeshRepo.mThread->mMutex);
-			gMeshRepo.mThread->mHeaderReqQ.push(req);
+		S32 offset = mOffset;
+		S32 size = mRequestedBytes;
 
-			return;
-		}
-		else
+		if (file.getSize() >= offset+size)
 		{
-			llwarns << "Unhandled status " << dumpResponse() << llendl;
+			LLMeshRepository::sCacheBytesWritten += size;
+			++LLMeshRepository::sCacheWrites;
+			file.seek(offset);
+			file.write(data, size);
 		}
 	}
-
-	S32 data_size = buffer->countAfter(channels.in(), NULL);
-
-	U8* data = NULL;
-
-	if (data_size > 0)
+	else
 	{
-		data = new U8[data_size];
-		buffer->readAfter(channels.in(), NULL, data, data_size);
+		LL_WARNS(LOG_MESH) << "Error during mesh decomposition processing.  ID:  " << mMeshID
+						   << ", Unknown reason.  Not retrying."
+						   << LL_ENDL;
+		// *TODO:  Mark mesh unavailable on error
 	}
+}
 
-	LLMeshRepository::sBytesReceived += llmin(data_size, 4096);
+LLMeshPhysicsShapeHandler::~LLMeshPhysicsShapeHandler()
+{
+		llassert(mProcessed);
+}
 
-	bool success = gMeshRepo.mThread->headerReceived(mMeshParams, data, data_size);
-	
-	llassert(success);
+void LLMeshPhysicsShapeHandler::processFailure(LLCore::HttpStatus status)
+{
+	LL_WARNS(LOG_MESH) << "Error during mesh physics shape handling.  ID:  " << mMeshID
+					   << ", Reason:  " << status.toString()
+					   << " (" << status.toTerseString() << ").  Not retrying."
+					   << LL_ENDL;
+	// *TODO:  Mark mesh unavailable on error
+}
 
-	if (!success)
-	{
-		llwarns << "Unable to parse mesh header: " << dumpResponse() << llendl;
-	}
-	else if (data && data_size > 0)
+void LLMeshPhysicsShapeHandler::processData(LLCore::BufferArray * body, U8 * data, S32 data_size)
+{
+	if ((! MESH_PHYS_SHAPE_PROCESS_FAILED) && gMeshRepo.mThread->physicsShapeReceived(mMeshID, data, data_size))
 	{
-		//header was successfully retrieved from sim, cache in vfs
-		LLUUID mesh_id = mMeshParams.getSculptID();
-		LLSD header = gMeshRepo.mThread->mMeshHeader[mesh_id];
+		// good fetch from sim, write to VFS for caching
+		LLVFile file(gVFS, mMeshID, LLAssetType::AT_MESH, LLVFile::WRITE);
 
-		S32 version = header["version"].asInteger();
+		S32 offset = mOffset;
+		S32 size = mRequestedBytes;
 
-		if (version <= MAX_MESH_VERSION)
+		if (file.getSize() >= offset+size)
 		{
-			std::stringstream str;
-
-			S32 lod_bytes = 0;
-
-			for (U32 i = 0; i < LLModel::LOD_PHYSICS; ++i)
-			{ //figure out how many bytes we'll need to reserve in the file
-				std::string lod_name = header_lod[i];
-				lod_bytes = llmax(lod_bytes, header[lod_name]["offset"].asInteger()+header[lod_name]["size"].asInteger());
-			}
-		
-			//just in case skin info or decomposition is at the end of the file (which it shouldn't be)
-			lod_bytes = llmax(lod_bytes, header["skin"]["offset"].asInteger() + header["skin"]["size"].asInteger());
-			lod_bytes = llmax(lod_bytes, header["physics_convex"]["offset"].asInteger() + header["physics_convex"]["size"].asInteger());
-
-			S32 header_bytes = (S32) gMeshRepo.mThread->mMeshHeaderSize[mesh_id];
-			S32 bytes = lod_bytes + header_bytes; 
-
-		
-			//it's possible for the remote asset to have more data than is needed for the local cache
-			//only allocate as much space in the VFS as is needed for the local cache
-			data_size = llmin(data_size, bytes);
-
-			LLVFile file(gVFS, mesh_id, LLAssetType::AT_MESH, LLVFile::WRITE);
-			if (file.getMaxSize() >= bytes || file.setMaxSize(bytes))
-			{
-				LLMeshRepository::sCacheBytesWritten += data_size;
-
-				file.write((const U8*) data, data_size);
-			
-				//zero out the rest of the file 
-				U8 block[4096];
-				memset(block, 0, 4096);
-
-				while (bytes-file.tell() > 4096)
-				{
-					file.write(block, 4096);
-				}
-
-				S32 remaining = bytes-file.tell();
-
-				if (remaining > 0)
-				{
-					file.write(block, remaining);
-				}
-			}
+			LLMeshRepository::sCacheBytesWritten += size;
+			++LLMeshRepository::sCacheWrites;
+			file.seek(offset);
+			file.write(data, size);
 		}
 	}
-
-	delete [] data;
+	else
+	{
+		LL_WARNS(LOG_MESH) << "Error during mesh physics shape processing.  ID:  " << mMeshID
+						   << ", Unknown reason.  Not retrying."
+						   << LL_ENDL;
+		// *TODO:  Mark mesh unavailable on error
+	}
 }
 
-
 LLMeshRepository::LLMeshRepository()
 : mMeshMutex(NULL),
   mMeshThreadCount(0),
-  mThread(NULL)
+  mThread(NULL),
+  mGetMeshVersion(2)
 {
 
 }
@@ -2325,7 +3029,7 @@ void LLMeshRepository::init()
 		apr_sleep(100);
 	}
 
-	
+	metrics_teleport_started_signal = LLViewerMessage::getInstance()->setTeleportStartedCallback(teleport_started);
 	
 	mThread = new LLMeshRepoThread();
 	mThread->start();
@@ -2333,11 +3037,13 @@ void LLMeshRepository::init()
 
 void LLMeshRepository::shutdown()
 {
-	llinfos << "Shutting down mesh repository." << llendl;
+	LL_INFOS(LOG_MESH) << "Shutting down mesh repository." << LL_ENDL;
+
+	metrics_teleport_started_signal.disconnect();
 
 	for (U32 i = 0; i < mUploads.size(); ++i)
 	{
-		llinfos << "Discard the pending mesh uploads " << llendl;
+		LL_INFOS(LOG_MESH) << "Discard the pending mesh uploads." << LL_ENDL;
 		mUploads[i]->discard() ; //discard the uploading requests.
 	}
 
@@ -2352,7 +3058,7 @@ void LLMeshRepository::shutdown()
 
 	for (U32 i = 0; i < mUploads.size(); ++i)
 	{
-		llinfos << "Waiting for pending mesh upload " << i << "/" << mUploads.size() << llendl;
+		LL_INFOS(LOG_MESH) << "Waiting for pending mesh upload " << (i + 1) << "/" << mUploads.size() << LL_ENDL;
 		while (!mUploads[i]->isStopped())
 		{
 			apr_sleep(10);
@@ -2365,7 +3071,7 @@ void LLMeshRepository::shutdown()
 	delete mMeshMutex;
 	mMeshMutex = NULL;
 
-	llinfos << "Shutting down decomposition system." << llendl;
+	LL_INFOS(LOG_MESH) << "Shutting down decomposition system." << LL_ENDL;
 
 	if (mDecompThread)
 	{
@@ -2380,6 +3086,9 @@ void LLMeshRepository::shutdown()
 //called in the main thread.
 S32 LLMeshRepository::update()
 {
+	// Conditionally log a mesh metrics event
+	metricsUpdate();
+	
 	if(mUploadWaitList.empty())
 	{
 		return 0 ;
@@ -2399,7 +3108,12 @@ S32 LLMeshRepository::update()
 
 S32 LLMeshRepository::loadMesh(LLVOVolume* vobj, const LLVolumeParams& mesh_params, S32 detail, S32 last_lod)
 {
-	if (detail < 0 || detail > 4)
+	MESH_FASTTIMER_DEFBLOCK;
+	
+	// Manage time-to-load metrics for mesh download operations.
+	metricsProgress(1);
+
+	if (detail < 0 || detail >= 4)
 	{
 		return detail;
 	}
@@ -2477,9 +3191,32 @@ S32 LLMeshRepository::loadMesh(LLVOVolume* vobj, const LLVolumeParams& mesh_para
 
 void LLMeshRepository::notifyLoadedMeshes()
 { //called from main thread
+	MESH_FASTTIMER_DEFBLOCK;
 
-	LLMeshRepoThread::sMaxConcurrentRequests = gSavedSettings.getU32("MeshMaxConcurrentRequests");
-
+	if (1 == mGetMeshVersion)
+	{
+		// Legacy GetMesh operation with high connection concurrency
+		LLMeshRepoThread::sMaxConcurrentRequests = gSavedSettings.getU32("MeshMaxConcurrentRequests");
+		LLMeshRepoThread::sRequestHighWater = llclamp(2 * S32(LLMeshRepoThread::sMaxConcurrentRequests),
+													  REQUEST_HIGH_WATER_MIN,
+													  REQUEST_HIGH_WATER_MAX);
+		LLMeshRepoThread::sRequestLowWater = llclamp(LLMeshRepoThread::sRequestHighWater / 2,
+													 REQUEST_LOW_WATER_MIN,
+													 REQUEST_LOW_WATER_MAX);
+	}
+	else
+	{
+		// GetMesh2 operation with keepalives, etc.  With pipelining,
+		// we'll increase this.
+		LLMeshRepoThread::sMaxConcurrentRequests = gSavedSettings.getU32("Mesh2MaxConcurrentRequests");
+		LLMeshRepoThread::sRequestHighWater = llclamp(5 * S32(LLMeshRepoThread::sMaxConcurrentRequests),
+													  REQUEST2_HIGH_WATER_MIN,
+													  REQUEST2_HIGH_WATER_MAX);
+		LLMeshRepoThread::sRequestLowWater = llclamp(LLMeshRepoThread::sRequestHighWater / 2,
+													 REQUEST2_LOW_WATER_MIN,
+													 REQUEST2_LOW_WATER_MAX);
+	}
+	
 	//clean up completed upload threads
 	for (std::vector<LLMeshUploadThread*>::iterator iter = mUploads.begin(); iter != mUploads.end(); )
 	{
@@ -2556,26 +3293,46 @@ void LLMeshRepository::notifyLoadedMeshes()
 
 	//call completed callbacks on finished decompositions
 	mDecompThread->notifyCompleted();
-	
-	if (!mThread->mWaiting)
-	{ //curl thread is churning, wait for it to go idle
-		return;
-	}
 
-	static std::string region_name("never name a region this");
+	// For major operations, attempt to get the required locks
+	// without blocking and punt if they're not available.  The
+	// longest run of holdoffs is kept in sMaxLockHoldoffs just
+	// to collect the data.  In testing, I've never seen a value
+	// greater than 2 (written to log on exit).
+	{
+		LLMutexTrylock lock1(mMeshMutex);
+		LLMutexTrylock lock2(mThread->mMutex);
 
-	if (gAgent.getRegion())
-	{ //update capability url 
-		if (gAgent.getRegion()->getName() != region_name && gAgent.getRegion()->capabilitiesReceived())
+		static U32 hold_offs(0);
+		if (! lock1.isLocked() || ! lock2.isLocked())
 		{
-			region_name = gAgent.getRegion()->getName();
-			mGetMeshCapability = gAgent.getRegion()->getCapability("GetMesh");
+			// If we can't get the locks, skip and pick this up later.
+			++hold_offs;
+			sMaxLockHoldoffs = llmax(sMaxLockHoldoffs, hold_offs);
+			return;
+		}
+		hold_offs = 0;
+		
+		if (gAgent.getRegion())
+		{
+			// Update capability urls
+			static std::string region_name("never name a region this");
+			
+			if (gAgent.getRegion()->getName() != region_name && gAgent.getRegion()->capabilitiesReceived())
+			{
+				region_name = gAgent.getRegion()->getName();
+				const bool use_v1(gSavedSettings.getBOOL("MeshUseGetMesh1"));
+				const std::string mesh1(gAgent.getRegion()->getCapability("GetMesh"));
+				const std::string mesh2(gAgent.getRegion()->getCapability("GetMesh2"));
+				mGetMeshVersion = (mesh2.empty() || use_v1) ? 1 : 2;
+				mThread->setGetMeshCaps(mesh1, mesh2, mGetMeshVersion);
+				LL_DEBUGS(LOG_MESH) << "Retrieving caps for region '" << region_name
+									<< "', GetMesh2:  " << mesh2
+									<< ", GetMesh:  " << mesh1
+									<< ", using version:  " << mGetMeshVersion
+									<< LL_ENDL;
+			}
 		}
-	}
-
-	{
-		LLMutexLock lock1(mMeshMutex);
-		LLMutexLock lock2(mThread->mMutex);
 		
 		//popup queued error messages from background threads
 		while (!mUploadErrorQ.empty())
@@ -2584,47 +3341,55 @@ void LLMeshRepository::notifyLoadedMeshes()
 			mUploadErrorQ.pop();
 		}
 
-		S32 push_count = LLMeshRepoThread::sMaxConcurrentRequests-(LLMeshRepoThread::sActiveHeaderRequests+LLMeshRepoThread::sActiveLODRequests);
-
-		if (push_count > 0)
+		S32 active_count = LLMeshRepoThread::sActiveHeaderRequests + LLMeshRepoThread::sActiveLODRequests;
+		if (active_count < LLMeshRepoThread::sRequestLowWater)
 		{
-			//calculate "score" for pending requests
-
-			//create score map
-			std::map<LLUUID, F32> score_map;
+			S32 push_count = LLMeshRepoThread::sRequestHighWater - active_count;
 
-			for (U32 i = 0; i < 4; ++i)
+			if (mPendingRequests.size() > push_count)
 			{
-				for (mesh_load_map::iterator iter = mLoadingMeshes[i].begin();  iter != mLoadingMeshes[i].end(); ++iter)
+				// More requests than the high-water limit allows so
+				// sort and forward the most important.
+
+				//calculate "score" for pending requests
+
+				//create score map
+				std::map<LLUUID, F32> score_map;
+
+				for (U32 i = 0; i < 4; ++i)
 				{
-					F32 max_score = 0.f;
-					for (std::set<LLUUID>::iterator obj_iter = iter->second.begin(); obj_iter != iter->second.end(); ++obj_iter)
+					for (mesh_load_map::iterator iter = mLoadingMeshes[i].begin();  iter != mLoadingMeshes[i].end(); ++iter)
 					{
-						LLViewerObject* object = gObjectList.findObject(*obj_iter);
-
-						if (object)
+						F32 max_score = 0.f;
+						for (std::set<LLUUID>::iterator obj_iter = iter->second.begin(); obj_iter != iter->second.end(); ++obj_iter)
 						{
-							LLDrawable* drawable = object->mDrawable;
-							if (drawable)
+							LLViewerObject* object = gObjectList.findObject(*obj_iter);
+
+							if (object)
 							{
-								F32 cur_score = drawable->getRadius()/llmax(drawable->mDistanceWRTCamera, 1.f);
-								max_score = llmax(max_score, cur_score);
+								LLDrawable* drawable = object->mDrawable;
+								if (drawable)
+								{
+									F32 cur_score = drawable->getRadius()/llmax(drawable->mDistanceWRTCamera, 1.f);
+									max_score = llmax(max_score, cur_score);
+								}
 							}
 						}
-					}
 				
-					score_map[iter->first.getSculptID()] = max_score;
+						score_map[iter->first.getSculptID()] = max_score;
+					}
 				}
-			}
 
-			//set "score" for pending requests
-			for (std::vector<LLMeshRepoThread::LODRequest>::iterator iter = mPendingRequests.begin(); iter != mPendingRequests.end(); ++iter)
-			{
-				iter->mScore = score_map[iter->mMeshParams.getSculptID()];
-			}
+				//set "score" for pending requests
+				for (std::vector<LLMeshRepoThread::LODRequest>::iterator iter = mPendingRequests.begin(); iter != mPendingRequests.end(); ++iter)
+				{
+					iter->mScore = score_map[iter->mMeshParams.getSculptID()];
+				}
 
-			//sort by "score"
-			std::sort(mPendingRequests.begin(), mPendingRequests.end(), LLMeshRepoThread::CompareScoreGreater());
+				//sort by "score"
+				std::partial_sort(mPendingRequests.begin(), mPendingRequests.begin() + push_count,
+								  mPendingRequests.end(), LLMeshRepoThread::CompareScoreGreater());
+			}
 
 			while (!mPendingRequests.empty() && push_count > 0)
 			{
@@ -2678,9 +3443,8 @@ void LLMeshRepository::notifySkinInfoReceived(LLMeshSkinInfo& info)
 				vobj->notifyMeshLoaded();
 			}
 		}
+		mLoadingSkins.erase(info.mMeshID);
 	}
-
-	mLoadingSkins.erase(info.mMeshID);
 }
 
 void LLMeshRepository::notifyDecompositionReceived(LLModel::Decomposition* decomp)
@@ -2689,14 +3453,14 @@ void LLMeshRepository::notifyDecompositionReceived(LLModel::Decomposition* decom
 	if (iter == mDecompositionMap.end())
 	{ //just insert decomp into map
 		mDecompositionMap[decomp->mMeshID] = decomp;
+		mLoadingDecompositions.erase(decomp->mMeshID);
 	}
 	else
 	{ //merge decomp with existing entry
 		iter->second->merge(decomp);
+		mLoadingDecompositions.erase(decomp->mMeshID);
 		delete decomp;
 	}
-
-	mLoadingDecompositions.erase(decomp->mMeshID);
 }
 
 void LLMeshRepository::notifyMeshLoaded(const LLVolumeParams& mesh_params, LLVolume* volume)
@@ -2711,7 +3475,8 @@ void LLMeshRepository::notifyMeshLoaded(const LLVolumeParams& mesh_params, LLVol
 		//make sure target volume is still valid
 		if (volume->getNumVolumeFaces() <= 0)
 		{
-			llwarns << "Mesh loading returned empty volume." << llendl;
+			LL_WARNS(LOG_MESH) << "Mesh loading returned empty volume.  ID:  " << mesh_params.getSculptID()
+							   << LL_ENDL;
 		}
 		
 		{ //update system volume
@@ -2724,7 +3489,8 @@ void LLMeshRepository::notifyMeshLoaded(const LLVolumeParams& mesh_params, LLVol
 			}
 			else
 			{
-				llwarns << "Couldn't find system volume for given mesh." << llendl;
+				LL_WARNS(LOG_MESH) << "Couldn't find system volume for mesh " << mesh_params.getSculptID()
+								   << LL_ENDL;
 			}
 		}
 
@@ -2778,6 +3544,8 @@ S32 LLMeshRepository::getActualMeshLOD(const LLVolumeParams& mesh_params, S32 lo
 
 const LLMeshSkinInfo* LLMeshRepository::getSkinInfo(const LLUUID& mesh_id, const LLVOVolume* requesting_obj)
 {
+	MESH_FASTTIMER_DEFBLOCK;
+
 	if (mesh_id.notNull())
 	{
 		skin_map::iterator iter = mSkinMap.find(mesh_id);
@@ -2804,6 +3572,8 @@ const LLMeshSkinInfo* LLMeshRepository::getSkinInfo(const LLUUID& mesh_id, const
 
 void LLMeshRepository::fetchPhysicsShape(const LLUUID& mesh_id)
 {
+	MESH_FASTTIMER_DEFBLOCK;
+
 	if (mesh_id.notNull())
 	{
 		LLModel::Decomposition* decomp = NULL;
@@ -2821,6 +3591,7 @@ void LLMeshRepository::fetchPhysicsShape(const LLUUID& mesh_id)
 			std::set<LLUUID>::iterator iter = mLoadingPhysicsShapes.find(mesh_id);
 			if (iter == mLoadingPhysicsShapes.end())
 			{ //no request pending for this skin info
+				// *FIXME:  Nothing ever deletes entries, can't be right
 				mLoadingPhysicsShapes.insert(mesh_id);
 				mPendingPhysicsShapeRequests.push(mesh_id);
 			}
@@ -2831,6 +3602,8 @@ void LLMeshRepository::fetchPhysicsShape(const LLUUID& mesh_id)
 
 LLModel::Decomposition* LLMeshRepository::getDecomposition(const LLUUID& mesh_id)
 {
+	MESH_FASTTIMER_DEFBLOCK;
+
 	LLModel::Decomposition* ret = NULL;
 
 	if (mesh_id.notNull())
@@ -2893,6 +3666,8 @@ bool LLMeshRepository::hasPhysicsShape(const LLUUID& mesh_id)
 
 LLSD& LLMeshRepository::getMeshHeader(const LLUUID& mesh_id)
 {
+	MESH_FASTTIMER_DEFBLOCK;
+
 	return mThread->getMeshHeader(mesh_id);
 }
 
@@ -2914,7 +3689,7 @@ LLSD& LLMeshRepoThread::getMeshHeader(const LLUUID& mesh_id)
 
 
 void LLMeshRepository::uploadModel(std::vector<LLModelInstance>& data, LLVector3& scale, bool upload_textures,
-									bool upload_skin, bool upload_joints, std::string upload_url, bool do_upload,
+								   bool upload_skin, bool upload_joints, std::string upload_url, bool do_upload,
 								   LLHandle<LLWholeModelFeeObserver> fee_observer, LLHandle<LLWholeModelUploadObserver> upload_observer)
 {
 	LLMeshUploadThread* thread = new LLMeshUploadThread(data, scale, upload_textures, upload_skin, upload_joints, upload_url, 
@@ -2943,7 +3718,6 @@ S32 LLMeshRepository::getMeshSize(const LLUUID& mesh_id, S32 lod)
 	}
 
 	return -1;
-
 }
 
 void LLMeshUploadThread::decomposeMeshMatrix(LLMatrix4& transformation,
@@ -3208,7 +3982,7 @@ void LLPhysicsDecomp::setMeshData(LLCDMeshData& mesh, bool vertex_based)
 
 		if (ret)
 		{
-			llerrs << "Convex Decomposition thread valid but could not set mesh data" << llendl;
+			LL_ERRS(LOG_MESH) << "Convex Decomposition thread valid but could not set mesh data." << LL_ENDL;
 		}
 	}
 }
@@ -3284,7 +4058,8 @@ void LLPhysicsDecomp::doDecomposition()
 
 	if (ret)
 	{
-		llwarns << "Convex Decomposition thread valid but could not execute stage " << stage << llendl;
+		LL_WARNS(LOG_MESH) << "Convex Decomposition thread valid but could not execute stage " << stage << "."
+						   << LL_ENDL;
 		LLMutexLock lock(mMutex);
 
 		mCurRequest->mHull.clear();
@@ -3413,9 +4188,9 @@ void LLPhysicsDecomp::doDecompositionSingleHull()
 	setMeshData(mesh, true);
 
 	LLCDResult ret = decomp->buildSingleHull() ;
-	if(ret)
+	if (ret)
 	{
-		llwarns << "Could not execute decomposition stage when attempting to create single hull." << llendl;
+		LL_WARNS(LOG_MESH) << "Could not execute decomposition stage when attempting to create single hull." << LL_ENDL;
 		make_box(mCurRequest);
 	}
 	else
@@ -3720,3 +4495,63 @@ bool LLMeshRepository::meshRezEnabled()
 	}
 	return false;
 }
+
+// Threading:  main thread only
+// static
+void LLMeshRepository::metricsStart()
+{
+	++metrics_teleport_start_count;
+	sQuiescentTimer.start(0);
+}
+
+// Threading:  main thread only
+// static
+void LLMeshRepository::metricsStop()
+{
+	sQuiescentTimer.stop(0);
+}
+
+// Threading:  main thread only
+// static
+void LLMeshRepository::metricsProgress(unsigned int this_count)
+{
+	static bool first_start(true);
+
+	if (first_start)
+	{
+		metricsStart();
+		first_start = false;
+	}
+	sQuiescentTimer.ringBell(0, this_count);
+}
+
+// Threading:  main thread only
+// static
+void LLMeshRepository::metricsUpdate()
+{
+	F64 started, stopped;
+	U64 total_count(U64L(0)), user_cpu(U64L(0)), sys_cpu(U64L(0));
+	
+	if (sQuiescentTimer.isExpired(0, started, stopped, total_count, user_cpu, sys_cpu))
+	{
+		LLSD metrics;
+
+		metrics["reason"] = "Mesh Download Quiescent";
+		metrics["scope"] = metrics_teleport_start_count > 1 ? "Teleport" : "Login";
+		metrics["start"] = started;
+		metrics["stop"] = stopped;
+		metrics["fetches"] = LLSD::Integer(total_count);
+		metrics["teleports"] = LLSD::Integer(metrics_teleport_start_count);
+		metrics["user_cpu"] = double(user_cpu) / 1.0e6;
+		metrics["sys_cpu"] = double(sys_cpu) / 1.0e6;
+		LL_INFOS(LOG_MESH) << "EventMarker " << metrics << LL_ENDL;
+	}
+}
+
+// Threading:  main thread only
+// static
+void teleport_started()
+{
+	LLMeshRepository::metricsStart();
+}
+
diff --git a/indra/newview/llmeshrepository.h b/indra/newview/llmeshrepository.h
index 8eaf691d6f..39280bea3a 100755
--- a/indra/newview/llmeshrepository.h
+++ b/indra/newview/llmeshrepository.h
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2001&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2010, Linden Research, Inc.
+ * Copyright (C) 2010-2013, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -32,6 +32,12 @@
 #include "lluuid.h"
 #include "llviewertexture.h"
 #include "llvolume.h"
+#include "lldeadmantimer.h"
+#include "httpcommon.h"
+#include "httprequest.h"
+#include "httpoptions.h"
+#include "httpheaders.h"
+#include "httphandler.h"
 
 #define LLCONVEXDECOMPINTER_STATIC 1
 
@@ -39,8 +45,6 @@
 #include "lluploadfloaterobservers.h"
 
 class LLVOVolume;
-class LLMeshResponder;
-class LLCurlRequest;
 class LLMutex;
 class LLCondition;
 class LLVFS;
@@ -215,17 +219,17 @@ class LLMeshRepoThread : public LLThread
 {
 public:
 
-	static S32 sActiveHeaderRequests;
-	static S32 sActiveLODRequests;
+	volatile static S32 sActiveHeaderRequests;
+	volatile static S32 sActiveLODRequests;
 	static U32 sMaxConcurrentRequests;
+	static S32 sRequestLowWater;
+	static S32 sRequestHighWater;
+	static S32 sRequestWaterLevel;			// Stats-use only, may read outside of thread
 
-	LLCurlRequest* mCurlRequest;
 	LLMutex*	mMutex;
 	LLMutex*	mHeaderMutex;
 	LLCondition* mSignal;
 
-	bool mWaiting;
-
 	//map of known mesh headers
 	typedef std::map<LLUUID, LLSD> mesh_header_map;
 	mesh_header_map mMeshHeader;
@@ -287,8 +291,8 @@ public:
 	//set of requested skin info
 	std::set<LLUUID> mSkinRequests;
 	
-	//queue of completed skin info requests
-	std::queue<LLMeshSkinInfo> mSkinInfoQ;
+	// list of completed skin info requests
+	std::list<LLMeshSkinInfo> mSkinInfoQ;
 
 	//set of requested decompositions
 	std::set<LLUUID> mDecompositionRequests;
@@ -296,8 +300,8 @@ public:
 	//set of requested physics shapes
 	std::set<LLUUID> mPhysicsShapeRequests;
 
-	//queue of completed Decomposition info requests
-	std::queue<LLModel::Decomposition*> mDecompositionQ;
+	// list of completed Decomposition info requests
+	std::list<LLModel::Decomposition*> mDecompositionQ;
 
 	//queue of requested headers
 	std::queue<HeaderRequest> mHeaderReqQ;
@@ -315,7 +319,23 @@ public:
 	typedef std::map<LLVolumeParams, std::vector<S32> > pending_lod_map;
 	pending_lod_map mPendingLOD;
 
-	static std::string constructUrl(LLUUID mesh_id);
+	// llcorehttp library interface objects.
+	LLCore::HttpStatus					mHttpStatus;
+	LLCore::HttpRequest *				mHttpRequest;
+	LLCore::HttpOptions *				mHttpOptions;
+	LLCore::HttpOptions *				mHttpLargeOptions;
+	LLCore::HttpHeaders *				mHttpHeaders;
+	LLCore::HttpRequest::policy_t		mHttpPolicyClass;
+	LLCore::HttpRequest::policy_t		mHttpLegacyPolicyClass;
+	LLCore::HttpRequest::policy_t		mHttpLargePolicyClass;
+	LLCore::HttpRequest::priority_t		mHttpPriority;
+
+	typedef std::set<LLCore::HttpHandler *> http_request_set;
+	http_request_set					mHttpRequestSet;			// Outstanding HTTP requests
+
+	std::string mGetMeshCapability;
+	std::string mGetMesh2Capability;
+	int mGetMeshVersion;
 
 	LLMeshRepoThread();
 	~LLMeshRepoThread();
@@ -325,8 +345,8 @@ public:
 	void lockAndLoadMeshLOD(const LLVolumeParams& mesh_params, S32 lod);
 	void loadMeshLOD(const LLVolumeParams& mesh_params, S32 lod);
 
-	bool fetchMeshHeader(const LLVolumeParams& mesh_params, U32& count);
-	bool fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod, U32& count);
+	bool fetchMeshHeader(const LLVolumeParams& mesh_params);
+	bool fetchMeshLOD(const LLVolumeParams& mesh_params, S32 lod);
 	bool headerReceived(const LLVolumeParams& mesh_params, U8* data, S32 data_size);
 	bool lodReceived(const LLVolumeParams& mesh_params, S32 lod, U8* data, S32 data_size);
 	bool skinInfoReceived(const LLUUID& mesh_id, U8* data, S32 data_size);
@@ -358,9 +378,37 @@ public:
 	static void incActiveHeaderRequests();
 	static void decActiveHeaderRequests();
 
+	// Set the caps strings and preferred version for constructing
+	// mesh fetch URLs.
+	//
+	// Mutex:  must be holding mMutex when called
+	void setGetMeshCaps(const std::string & get_mesh1,
+						const std::string & get_mesh2,
+						int pref_version);
+
+	// Mutex:  acquires mMutex
+	void constructUrl(LLUUID mesh_id, std::string * url, int * version);
+
+private:
+	// Issue a GET request to a URL with 'Range' header using
+	// the correct policy class and other attributes.  If an invalid
+	// handle is returned, the request failed and caller must retry
+	// or dispose of handler.
+	//
+	// Threads:  Repo thread only
+	LLCore::HttpHandle getByteRange(const std::string & url, int cap_version,
+									size_t offset, size_t len, 
+									LLCore::HttpHandler * handler);
 };
 
-class LLMeshUploadThread : public LLThread 
+
+// Class whose instances represent a single upload-type request for
+// meshes:  one fee query or one actual upload attempt.  Yes, it creates
+// a unique thread for that single request.  As it is 1:1, it can also
+// trivially serve as the HttpHandler object for request completion
+// notifications.
+
+class LLMeshUploadThread : public LLThread, public LLCore::HttpHandler 
 {
 private:
 	S32 mMeshUploadTimeOut ; //maximum time in seconds to execute an uploading request.
@@ -381,44 +429,41 @@ public:
 	};
 
 	LLPointer<DecompRequest> mFinalDecomp;
-	bool mPhysicsComplete;
+	volatile bool	mPhysicsComplete;
 
 	typedef std::map<LLPointer<LLModel>, std::vector<LLVector3> > hull_map;
-	hull_map mHullMap;
+	hull_map		mHullMap;
 
 	typedef std::vector<LLModelInstance> instance_list;
-	instance_list mInstanceList;
+	instance_list	mInstanceList;
 
 	typedef std::map<LLPointer<LLModel>, instance_list> instance_map;
-	instance_map mInstance;
+	instance_map	mInstance;
 
-	LLMutex*					mMutex;
-	LLCurlRequest* mCurlRequest;
+	LLMutex*		mMutex;
 	S32				mPendingUploads;
 	LLVector3		mOrigin;
 	bool			mFinished;	
 	bool			mUploadTextures;
 	bool			mUploadSkin;
 	bool			mUploadJoints;
-	BOOL            mDiscarded ;
+	volatile bool	mDiscarded;
 
 	LLHost			mHost;
 	std::string		mWholeModelFeeCapability;
 	std::string		mWholeModelUploadURL;
 
 	LLMeshUploadThread(instance_list& data, LLVector3& scale, bool upload_textures,
-			bool upload_skin, bool upload_joints, std::string upload_url, bool do_upload = true,
-					   LLHandle<LLWholeModelFeeObserver> fee_observer= (LLHandle<LLWholeModelFeeObserver>()), LLHandle<LLWholeModelUploadObserver> upload_observer = (LLHandle<LLWholeModelUploadObserver>()));
+					   bool upload_skin, bool upload_joints, const std::string & upload_url, bool do_upload = true,
+					   LLHandle<LLWholeModelFeeObserver> fee_observer = (LLHandle<LLWholeModelFeeObserver>()),
+					   LLHandle<LLWholeModelUploadObserver> upload_observer = (LLHandle<LLWholeModelUploadObserver>()));
 	~LLMeshUploadThread();
 
-	void startRequest() { ++mPendingUploads; }
-	void stopRequest() { --mPendingUploads; }
-
-	bool finished() { return mFinished; }
+	bool finished() const { return mFinished; }
 	virtual void run();
 	void preStart();
 	void discard() ;
-	BOOL isDiscarded();
+	bool isDiscarded() const;
 
 	void generateHulls();
 
@@ -435,11 +480,23 @@ public:
 	void setFeeObserverHandle(LLHandle<LLWholeModelFeeObserver> observer_handle) { mFeeObserverHandle = observer_handle; }
 	void setUploadObserverHandle(LLHandle<LLWholeModelUploadObserver> observer_handle) { mUploadObserverHandle = observer_handle; }
 
+	// Inherited from LLCore::HttpHandler
+	virtual void onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response);
+
 private:
 	LLHandle<LLWholeModelFeeObserver> mFeeObserverHandle;
 	LLHandle<LLWholeModelUploadObserver> mUploadObserverHandle;
 
 	bool mDoUpload; // if FALSE only model data will be requested, otherwise the model will be uploaded
+	LLSD mModelData;
+	
+	// llcorehttp library interface objects.
+	LLCore::HttpStatus					mHttpStatus;
+	LLCore::HttpRequest *				mHttpRequest;
+	LLCore::HttpOptions *				mHttpOptions;
+	LLCore::HttpHeaders *				mHttpHeaders;
+	LLCore::HttpRequest::policy_t		mHttpPolicyClass;
+	LLCore::HttpRequest::priority_t		mHttpPriority;
 };
 
 class LLMeshRepository
@@ -448,21 +505,28 @@ public:
 
 	//metrics
 	static U32 sBytesReceived;
-	static U32 sHTTPRequestCount;
-	static U32 sHTTPRetryCount;
+	static U32 sMeshRequestCount;				// Total request count, http or cached, all component types
+	static U32 sHTTPRequestCount;				// Http GETs issued (not large)
+	static U32 sHTTPLargeRequestCount;			// Http GETs issued for large requests
+	static U32 sHTTPRetryCount;					// Total request retries whether successful or failed
+	static U32 sHTTPErrorCount;					// Requests ending in error
 	static U32 sLODPending;
 	static U32 sLODProcessing;
 	static U32 sCacheBytesRead;
 	static U32 sCacheBytesWritten;
-	static U32 sPeakKbps;
+	static U32 sCacheReads;						
+	static U32 sCacheWrites;
+	static U32 sMaxLockHoldoffs;				// Maximum sequential locking failures
 	
+	static LLDeadmanTimer sQuiescentTimer;		// Time-to-complete-mesh-downloads after significant events
+
 	static F32 getStreamingCost(LLSD& header, F32 radius, S32* bytes = NULL, S32* visible_bytes = NULL, S32 detail = -1, F32 *unscaled_value = NULL);
 
 	LLMeshRepository();
 
 	void init();
 	void shutdown();
-	S32 update() ;
+	S32 update();
 
 	//mesh management functions
 	S32 loadMesh(LLVOVolume* volume, const LLVolumeParams& mesh_params, S32 detail = 0, S32 last_lod = -1);
@@ -495,6 +559,12 @@ public:
 
 	S32 getMeshSize(const LLUUID& mesh_id, S32 lod);
 
+	// Quiescent timer management, main thread only.
+	static void metricsStart();
+	static void metricsStop();
+	static void metricsProgress(unsigned int count);
+	static void metricsUpdate();
+	
 	typedef std::map<LLVolumeParams, std::set<LLUUID> > mesh_load_map;
 	mesh_load_map mLoadingMeshes[4];
 	
@@ -556,8 +626,7 @@ public:
 	void uploadError(LLSD& args);
 	void updateInventory(inventory_data data);
 
-	std::string mGetMeshCapability;
-
+	int mGetMeshVersion;		// Shadows value in LLMeshRepoThread
 };
 
 extern LLMeshRepository gMeshRepo;
diff --git a/indra/newview/lltexturefetch.cpp b/indra/newview/lltexturefetch.cpp
index d0ab9f55ff..6ed54ce019 100755
--- a/indra/newview/lltexturefetch.cpp
+++ b/indra/newview/lltexturefetch.cpp
@@ -1606,8 +1606,8 @@ bool LLTextureFetchWorker::doWork(S32 param)
 				}
 				else
 				{
-					llinfos << "other: HTTP GET failed for: " << mUrl
-							<< " Status: " << mGetStatus.toHex()
+					llinfos << "HTTP GET failed for: " << mUrl
+							<< " Status: " << mGetStatus.toTerseString()
 							<< " Reason: '" << mGetReason << "'"
 							<< llendl;
 				}
@@ -1987,7 +1987,7 @@ void LLTextureFetchWorker::onCompleted(LLCore::HttpHandle handle, LLCore::HttpRe
 	}
 	
 	LL_DEBUGS("Texture") << "HTTP COMPLETE: " << mID
-						 << " status: " << status.toHex()
+						 << " status: " << status.toTerseString()
 						 << " '" << status.toString() << "'"
 						 << llendl;
 
@@ -2006,7 +2006,9 @@ void LLTextureFetchWorker::onCompleted(LLCore::HttpHandle handle, LLCore::HttpRe
 		success = false;
 		if (mFTType != FTT_MAP_TILE) // missing map tiles are normal, don't complain about them.
 		{
-			llwarns << mID << " CURL GET FAILED, status: " << status.toHex()
+			std::string reason(status.toString());
+			setGetStatus(status, reason);
+			llwarns << "CURL GET FAILED, status: " << status.toTerseString()
 					<< " reason: " << reason << llendl;
 		}
 	}
@@ -2505,11 +2507,10 @@ LLTextureFetch::LLTextureFetch(LLTextureCache* cache, LLImageDecodeThread* image
 	mHttpOptionsWithHeaders = new LLCore::HttpOptions;
 	mHttpOptionsWithHeaders->setWantHeaders(true);
 	mHttpHeaders = new LLCore::HttpHeaders;
-	// *TODO: Should this be 'image/j2c' instead of 'image/x-j2c' ?
-	mHttpHeaders->append(HTTP_OUT_HEADER_ACCEPT, HTTP_CONTENT_IMAGE_X_J2C);
+	mHttpHeaders->append("Accept", "image/x-j2c");
 	mHttpMetricsHeaders = new LLCore::HttpHeaders;
-	mHttpMetricsHeaders->append(HTTP_OUT_HEADER_CONTENT_TYPE, HTTP_CONTENT_LLSD_XML);
-	mHttpPolicyClass = LLAppViewer::instance()->getAppCoreHttp().getPolicyDefault();
+	mHttpMetricsHeaders->append("Content-Type", "application/llsd+xml");
+	mHttpPolicyClass = LLAppViewer::instance()->getAppCoreHttp().getPolicy(LLAppCoreHttp::AP_TEXTURE);
 }
 
 LLTextureFetch::~LLTextureFetch()
@@ -3884,7 +3885,7 @@ public:
 		else
 		{
 			LL_WARNS("Texture") << "Error delivering asset metrics to grid.  Status:  "
-								<< status.toHex()
+								<< status.toTerseString()
 								<< ", Reason:  " << status.toString() << LL_ENDL;
 		}
 	}
@@ -4153,8 +4154,7 @@ void LLTextureFetchDebugger::init()
 	if (! mHttpHeaders)
 	{
 		mHttpHeaders = new LLCore::HttpHeaders;
-		// *TODO: Should this be 'image/j2c' instead of 'image/x-j2c' ?
-		mHttpHeaders->append(HTTP_OUT_HEADER_ACCEPT, HTTP_CONTENT_IMAGE_X_J2C);
+		mHttpHeaders->append("Accept", "image/x-j2c");
 	}
 }
 
@@ -4574,7 +4574,7 @@ S32 LLTextureFetchDebugger::fillCurlQueue()
 
 			LL_WARNS("Texture") << "Couldn't issue HTTP request in debugger for texture "
 								<< mFetchingHistory[i].mID
-								<< ", status: " << status.toHex()
+								<< ", status: " << status.toTerseString()
 								<< " reason:  " << status.toString()
 								<< LL_ENDL;
 			mFetchingHistory[i].mCurlState = FetchEntry::CURL_DONE;
@@ -4967,7 +4967,7 @@ void LLTextureFetchDebugger::callbackHTTP(FetchEntry & fetch, LLCore::HttpRespon
 	else //failed
 	{
 		llinfos << "Fetch Debugger : CURL GET FAILED,  ID = " << fetch.mID
-				<< ", status: " << status.toHex()
+				<< ", status: " << status.toTerseString()
 				<< " reason:  " << status.toString() << llendl;
 	}
 }
diff --git a/indra/newview/lltextureview.cpp b/indra/newview/lltextureview.cpp
index dea1c6c1b2..0582bf4162 100755
--- a/indra/newview/lltextureview.cpp
+++ b/indra/newview/lltextureview.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2001&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2012, Linden Research, Inc.
+ * Copyright (C) 2012-2013, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -49,6 +49,7 @@
 #include "llviewertexturelist.h"
 #include "llvovolume.h"
 #include "llviewerstats.h"
+#include "llmeshrepository.h"
 
 // For avatar texture view
 #include "llvoavatarself.h"
@@ -509,6 +510,8 @@ void LLGLTexMemBar::draw()
 	F32 total_texture_downloaded = (F32)gTotalTextureBytes / (1024 * 1024);
 	F32 total_object_downloaded = (F32)gTotalObjectBytes / (1024 * 1024);
 	U32 total_http_requests = LLAppViewer::getTextureFetch()->getTotalNumHTTPRequests();
+	F32 x_right = 0.0;
+	
 	//----------------------------------------------------------------------------
 	LLGLSUIDefault gls_ui;
 	LLColor4 text_color(1.f, 1.f, 1.f, 0.75f);
@@ -535,7 +538,7 @@ void LLGLTexMemBar::draw()
 					cache_max_usage);
 	//, cache_entries, cache_max_entries
 
-	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*4,
+	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*5,
 											 text_color, LLFontGL::LEFT, LLFontGL::TOP);
 
 	U32 cache_read(0U), cache_write(0U), res_wait(0U);
@@ -549,13 +552,12 @@ void LLGLTexMemBar::draw()
 					cache_write,
 					res_wait);
 
-	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*3,
+	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*4,
 											 text_color, LLFontGL::LEFT, LLFontGL::TOP);
 
-	S32 left = 0 ;
 	//----------------------------------------------------------------------------
 
-	text = llformat("Textures: %d Fetch: %d(%d) Pkts:%d(%d) Cache R/W: %d/%d LFS:%d RAW:%d HTP:%d DEC:%d CRE:%d",
+	text = llformat("Textures: %d Fetch: %d(%d) Pkts:%d(%d) Cache R/W: %d/%d LFS:%d RAW:%d HTP:%d DEC:%d CRE:%d ",
 					gTextureList.getNumImages(),
 					LLAppViewer::getTextureFetch()->getNumRequests(), LLAppViewer::getTextureFetch()->getNumDeletes(),
 					LLAppViewer::getTextureFetch()->mPacketCount, LLAppViewer::getTextureFetch()->mBadPacketCount, 
@@ -566,19 +568,30 @@ void LLGLTexMemBar::draw()
 					LLAppViewer::getImageDecodeThread()->getPending(), 
 					gTextureList.mCreateTextureList.size());
 
-	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*2,
-									 text_color, LLFontGL::LEFT, LLFontGL::TOP);
-
+	x_right = 550.0;
+	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*3,
+											 text_color, LLFontGL::LEFT, LLFontGL::TOP,
+											 LLFontGL::NORMAL, LLFontGL::NO_SHADOW, S32_MAX, S32_MAX,
+											 &x_right, FALSE);
 
-	left = 550;
 	F32 bandwidth = LLAppViewer::getTextureFetch()->getTextureBandwidth();
 	F32 max_bandwidth = gSavedSettings.getF32("ThrottleBandwidthKBPS");
-	color = bandwidth > max_bandwidth ? LLColor4::red : bandwidth > max_bandwidth*.75f ? LLColor4::yellow : text_color;
+	color = bandwidth > max_bandwidth ? LLColor4::red : bandwidth > max_bandwidth * .75f ? LLColor4::yellow : text_color;
 	color[VALPHA] = text_color[VALPHA];
-	text = llformat("BW:%.0f/%.0f",bandwidth, max_bandwidth);
-	LLFontGL::getFontMonospace()->renderUTF8(text, 0, left, v_offset + line_height*2,
+	text = llformat("BW:%.0f/%.0f", bandwidth, max_bandwidth);
+	LLFontGL::getFontMonospace()->renderUTF8(text, 0, x_right, v_offset + line_height*3,
 											 color, LLFontGL::LEFT, LLFontGL::TOP);
-	
+
+	// Mesh status line
+	text = llformat("Mesh: Reqs(Tot/Htp/Big): %u/%u/%u Rtr/Err: %u/%u Cread/Cwrite: %u/%u Low/At/High: %d/%d/%d",
+					LLMeshRepository::sMeshRequestCount, LLMeshRepository::sHTTPRequestCount, LLMeshRepository::sHTTPLargeRequestCount,
+					LLMeshRepository::sHTTPRetryCount, LLMeshRepository::sHTTPErrorCount,
+					LLMeshRepository::sCacheReads, LLMeshRepository::sCacheWrites,
+					LLMeshRepoThread::sRequestLowWater, LLMeshRepoThread::sRequestWaterLevel, LLMeshRepoThread::sRequestHighWater);
+	LLFontGL::getFontMonospace()->renderUTF8(text, 0, 0, v_offset + line_height*2,
+											 text_color, LLFontGL::LEFT, LLFontGL::TOP);
+
+	// Header for texture table columns
 	S32 dx1 = 0;
 	if (LLAppViewer::getTextureFetch()->mDebugPause)
 	{
@@ -621,7 +634,7 @@ BOOL LLGLTexMemBar::handleMouseDown(S32 x, S32 y, MASK mask)
 LLRect LLGLTexMemBar::getRequiredRect()
 {
 	LLRect rect;
-	rect.mTop = 50; //LLFontGL::getFontMonospace()->getLineHeight() * 6;
+	rect.mTop = 68; //LLFontGL::getFontMonospace()->getLineHeight() * 6;
 	return rect;
 }
 
diff --git a/indra/newview/llviewerregion.cpp b/indra/newview/llviewerregion.cpp
index e6cc75f1ce..76d155d5f2 100755
--- a/indra/newview/llviewerregion.cpp
+++ b/indra/newview/llviewerregion.cpp
@@ -4,7 +4,7 @@
  *
  * $LicenseInfo:firstyear=2000&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2010, Linden Research, Inc.
+ * Copyright (C) 2010-2013, Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -1653,6 +1653,7 @@ void LLViewerRegionImpl::buildCapabilityNames(LLSD& capabilityNames)
 
 	capabilityNames.append("GetDisplayNames");
 	capabilityNames.append("GetMesh");
+	capabilityNames.append("GetMesh2");
 	capabilityNames.append("GetObjectCost");
 	capabilityNames.append("GetObjectPhysicsData");
 	capabilityNames.append("GetTexture");