Merge branch 'DRTVWR-559' of https://bitbucket.org/lindenlab/viewer into DRTVWR-559

17 files changed, 538 insertions, 231 deletions

diff --git a/indra/llcommon/CMakeLists.txt b/indra/llcommon/CMakeLists.txt
index 59aa731af2..62307c6e26 100644
--- a/indra/llcommon/CMakeLists.txt
+++ b/indra/llcommon/CMakeLists.txt
@@ -29,6 +29,7 @@ include_directories(
 #     ${LLCOMMON_LIBRARIES})
 
 set(llcommon_SOURCE_FILES
+    commoncontrol.cpp
     indra_constants.cpp
     llallocator.cpp
     llallocator_heap_profile.cpp
@@ -130,6 +131,7 @@ set(llcommon_HEADER_FILES
 
     chrono.h
     classic_callback.h
+    commoncontrol.h
     ctype_workaround.h
     fix_macros.h
     indra_constants.h
diff --git a/indra/llcommon/commoncontrol.cpp b/indra/llcommon/commoncontrol.cpp
new file mode 100644
index 0000000000..81e66baf8c
--- /dev/null
+++ b/indra/llcommon/commoncontrol.cpp
@@ -0,0 +1,106 @@
+/**
+ * @file   commoncontrol.cpp
+ * @author Nat Goodspeed
+ * @date   2022-06-08
+ * @brief  Implementation for commoncontrol.
+ * 
+ * $LicenseInfo:firstyear=2022&license=viewerlgpl$
+ * Copyright (c) 2022, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "commoncontrol.h"
+// STL headers
+// std headers
+// external library headers
+// other Linden headers
+#include "llevents.h"
+#include "llsdutil.h"
+
+LLSD LL::CommonControl::access(const LLSD& params)
+{
+    // We can't actually introduce a link-time dependency on llxml, or on any
+    // global LLControlGroup (*koff* gSavedSettings *koff*) but we can issue a
+    // runtime query. If we're running as part of a viewer with
+    // LLViewerControlListener, we can use that to interact with any
+    // instantiated LLControGroup.
+    LLSD response;
+    {
+        LLEventStream reply("reply");
+        LLTempBoundListener connection = reply.listen("listener",
+                     [&response] (const LLSD& event)
+                     {
+                         response = event;
+                         return false;
+                     });
+        LLSD rparams{ params };
+        rparams["reply"] = reply.getName();
+        LLEventPumps::instance().obtain("LLViewerControl").post(rparams);
+    }
+    // LLViewerControlListener responds immediately. If it's listening at all,
+    // it will already have set response.
+    if (! response.isDefined())
+    {
+        LLTHROW(NoListener("No LLViewerControl listener instantiated"));
+    }
+    LLSD error{ response["error"] };
+    if (error.isDefined())
+    {
+        LLTHROW(ParamError(error));
+    }
+    response.erase("error");
+    response.erase("reqid");
+    return response;
+}
+
+/// set control group.key to defined default value
+LLSD LL::CommonControl::set_default(const std::string& group, const std::string& key)
+{
+    return access(llsd::map("op", "set",
+                            "group", group, "key", key))["value"];
+}
+
+/// set control group.key to specified value
+LLSD LL::CommonControl::set(const std::string& group, const std::string& key, const LLSD& value)
+{
+    return access(llsd::map("op", "set",
+                            "group", group, "key", key, "value", value))["value"];
+}
+
+/// toggle boolean control group.key
+LLSD LL::CommonControl::toggle(const std::string& group, const std::string& key)
+{
+    return access(llsd::map("op", "toggle",
+                            "group", group, "key", key))["value"];
+}
+
+/// get the definition for control group.key, (! isDefined()) if bad
+/// ["name"], ["type"], ["value"], ["comment"]
+LLSD LL::CommonControl::get_def(const std::string& group, const std::string& key)
+{
+    return access(llsd::map("op", "get",
+                            "group", group, "key", key));
+}
+
+/// get the value of control group.key
+LLSD LL::CommonControl::get(const std::string& group, const std::string& key)
+{
+    return access(llsd::map("op", "get",
+                            "group", group, "key", key))["value"];
+}
+
+/// get defined groups
+std::vector<std::string> LL::CommonControl::get_groups()
+{
+    auto groups{ access(llsd::map("op", "groups"))["groups"] };
+    return { groups.beginArray(), groups.endArray() };
+}
+
+/// get definitions for all variables in group
+LLSD LL::CommonControl::get_vars(const std::string& group)
+{
+    return access(llsd::map("op", "vars", "group", group))["vars"];
+}
diff --git a/indra/llcommon/commoncontrol.h b/indra/llcommon/commoncontrol.h
new file mode 100644
index 0000000000..07d4a45ac5
--- /dev/null
+++ b/indra/llcommon/commoncontrol.h
@@ -0,0 +1,75 @@
+/**
+ * @file   commoncontrol.h
+ * @author Nat Goodspeed
+ * @date   2022-06-08
+ * @brief  Access LLViewerControl LLEventAPI, if process has one.
+ * 
+ * $LicenseInfo:firstyear=2022&license=viewerlgpl$
+ * Copyright (c) 2022, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_COMMONCONTROL_H)
+#define LL_COMMONCONTROL_H
+
+#include <vector>
+#include "llexception.h"
+#include "llsd.h"
+
+namespace LL
+{
+    class CommonControl
+    {
+    public:
+        struct Error: public LLException
+        {
+            Error(const std::string& what): LLException(what) {}
+        };
+
+        /// Exception thrown if there's no LLViewerControl LLEventAPI
+        struct NoListener: public Error
+        {
+            NoListener(const std::string& what): Error(what) {}
+        };
+
+        struct ParamError: public Error
+        {
+            ParamError(const std::string& what): Error(what) {}
+        };
+
+        /// set control group.key to defined default value
+        static
+        LLSD set_default(const std::string& group, const std::string& key);
+
+        /// set control group.key to specified value
+        static
+        LLSD set(const std::string& group, const std::string& key, const LLSD& value);
+
+        /// toggle boolean control group.key
+        static
+        LLSD toggle(const std::string& group, const std::string& key);
+
+        /// get the definition for control group.key, (! isDefined()) if bad
+        /// ["name"], ["type"], ["value"], ["comment"]
+        static
+        LLSD get_def(const std::string& group, const std::string& key);
+
+        /// get the value of control group.key
+        static
+        LLSD get(const std::string& group, const std::string& key);
+
+        /// get defined groups
+        static
+        std::vector<std::string> get_groups();
+
+        /// get definitions for all variables in group
+        static
+        LLSD get_vars(const std::string& group);
+
+    private:
+        static
+        LLSD access(const LLSD& params);
+    };
+} // namespace LL
+
+#endif /* ! defined(LL_COMMONCONTROL_H) */
diff --git a/indra/llcommon/llapr.cpp b/indra/llcommon/llapr.cpp
index db94765871..b537102510 100644
--- a/indra/llcommon/llapr.cpp
+++ b/indra/llcommon/llapr.cpp
@@ -526,6 +526,7 @@ S32 LLAPRFile::seek(apr_file_t* file_handle, apr_seek_where_t where, S32 offset)
 //static
 S32 LLAPRFile::readEx(const std::string& filename, void *buf, S32 offset, S32 nbytes, LLVolatileAPRPool* pool)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	//*****************************************
 	LLAPRFilePoolScope scope(pool);
 	apr_file_t* file_handle = open(filename, scope.getVolatileAPRPool(), APR_READ|APR_BINARY); 
@@ -570,6 +571,7 @@ S32 LLAPRFile::readEx(const std::string& filename, void *buf, S32 offset, S32 nb
 //static
 S32 LLAPRFile::writeEx(const std::string& filename, void *buf, S32 offset, S32 nbytes, LLVolatileAPRPool* pool)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	apr_int32_t flags = APR_CREATE|APR_WRITE|APR_BINARY;
 	if (offset < 0)
 	{
diff --git a/indra/llcommon/llframetimer.cpp b/indra/llcommon/llframetimer.cpp
index 58af32f1af..1e9920746b 100644
--- a/indra/llcommon/llframetimer.cpp
+++ b/indra/llcommon/llframetimer.cpp
@@ -29,11 +29,6 @@
 
 #include "llframetimer.h"
 
-// We don't bother building a stand alone lib; we just need to include the one source file for Tracy support
-//#if LL_PROFILER_CONFIGURATION == LL_PROFILER_CONFIG_TRACY || LL_PROFILER_CONFIGURATION == LL_PROFILER_CONFIG_TRACY_FAST_TIMER
-//	#include "TracyClient.cpp"
-//#endif // LL_PROFILER_CONFIGURATION
-
 // Static members
 //LLTimer	LLFrameTimer::sInternalTimer;
 U64 LLFrameTimer::sStartTotalTime = totalTime();
diff --git a/indra/llcommon/llmemory.cpp b/indra/llcommon/llmemory.cpp
index 849867586a..749b66b472 100644
--- a/indra/llcommon/llmemory.cpp
+++ b/indra/llcommon/llmemory.cpp
@@ -35,6 +35,7 @@
 # include <sys/types.h>
 # include <mach/task.h>
 # include <mach/mach_init.h>
+#include <mach/mach_host.h>
 #elif LL_LINUX
 # include <unistd.h>
 #endif
@@ -109,6 +110,50 @@ void LLMemory::updateMemoryInfo()
 	{
 		sAvailPhysicalMemInKB = U32Kilobytes(0);
 	}
+
+#elif defined(LL_DARWIN)
+    task_vm_info info;
+    mach_msg_type_number_t  infoCount = TASK_VM_INFO_COUNT;
+    // MACH_TASK_BASIC_INFO reports the same resident_size, but does not tell us the reusable bytes or phys_footprint.
+    if (task_info(mach_task_self(), TASK_VM_INFO, reinterpret_cast<task_info_t>(&info), &infoCount) == KERN_SUCCESS)
+    {
+        // Our Windows definition of PagefileUsage is documented by Microsoft as "the total amount of
+        // memory that the memory manager has committed for a running process", which is rss.
+        sAllocatedPageSizeInKB = U32Bytes(info.resident_size);
+
+        // Activity Monitor => Inspect Process => Real Memory Size appears to report resident_size
+        // Activity monitor => main window memory column appears to report phys_footprint, which spot checks as at least 30% less.
+        //        I think that is because of compression, which isn't going to give us a consistent measurement. We want uncompressed totals.
+        //
+        // In between is resident_size - reusable. This is what Chrome source code uses, with source comments saying it is 'the "Real Memory" value
+        // reported for the app by the Memory Monitor in Instruments.' It is still about 8% bigger than phys_footprint.
+        //
+        // (On Windows, we use WorkingSetSize.)
+        sAllocatedMemInKB = U32Bytes(info.resident_size - info.reusable);
+     }
+    else
+    {
+        LL_WARNS() << "task_info failed" << LL_ENDL;
+    }
+
+    // Total installed and available physical memory are properties of the host, not just our process.
+    vm_statistics64_data_t vmstat;
+    mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
+    mach_port_t host = mach_host_self();
+    vm_size_t page_size;
+    host_page_size(host, &page_size);
+    kern_return_t result = host_statistics64(host, HOST_VM_INFO64, reinterpret_cast<host_info_t>(&vmstat), &count);
+    if (result == KERN_SUCCESS) {
+        // This is what Chrome reports as 'the "Physical Memory Free" value reported by the Memory Monitor in Instruments.'
+        // Note though that inactive pages are not included here and not yet free, but could become so under memory pressure.
+        sAvailPhysicalMemInKB = U32Bytes(vmstat.free_count * page_size);
+        sMaxPhysicalMemInKB = LLMemoryInfo::getHardwareMemSize();
+      }
+    else
+    {
+        LL_WARNS() << "task_info failed" << LL_ENDL;
+    }
+
 #else
 	//not valid for other systems for now.
 	sAllocatedMemInKB = U64Bytes(LLMemory::getCurrentRSS());
diff --git a/indra/llcommon/llprofiler.h b/indra/llcommon/llprofiler.h
index bc46128d21..c0f5868db3 100644
--- a/indra/llcommon/llprofiler.h
+++ b/indra/llcommon/llprofiler.h
@@ -134,6 +134,10 @@ extern thread_local bool gProfilerEnabled;
         #define LL_PROFILE_ZONE_ERR(name)               LL_PROFILE_ZONE_NAMED_COLOR( name, 0XFF0000  )  // RGB yellow
         #define LL_PROFILE_ZONE_INFO(name)              LL_PROFILE_ZONE_NAMED_COLOR( name, 0X00FFFF  )  // RGB cyan
         #define LL_PROFILE_ZONE_WARN(name)              LL_PROFILE_ZONE_NAMED_COLOR( name, 0x0FFFF00 )  // RGB red
+        //#define LL_PROFILE_ALLOC(ptr, size)             TracyAlloc(ptr, size) // memory allocation tracking currently not working
+        //#define LL_PROFILE_FREE(ptr)                    TracyFree(ptr)
+        #define LL_PROFILE_ALLOC(ptr, size)             (void)(ptr); (void)(size);
+        #define LL_PROFILE_FREE(ptr)                    (void)(ptr);
     #endif
 #else
     #define LL_PROFILER_FRAME_END
diff --git a/indra/llcommon/llqueuedthread.cpp b/indra/llcommon/llqueuedthread.cpp
index 8cef4293cd..155e32ebae 100644
--- a/indra/llcommon/llqueuedthread.cpp
+++ b/indra/llcommon/llqueuedthread.cpp
@@ -26,20 +26,26 @@
 #include "linden_common.h"
 #include "llqueuedthread.h"
 
+#include <chrono>
+
 #include "llstl.h"
 #include "lltimer.h"	// ms_sleep()
-#include "lltracethreadrecorder.h"
+#include "llmutex.h"
 
 //============================================================================
 
 // MAIN THREAD
 LLQueuedThread::LLQueuedThread(const std::string& name, bool threaded, bool should_pause) :
-	LLThread(name),
-	mThreaded(threaded),
-	mIdleThread(TRUE),
-	mNextHandle(0),
-	mStarted(FALSE)
+    LLThread(name),
+    mIdleThread(TRUE),
+    mNextHandle(0),
+    mStarted(FALSE),
+    mThreaded(threaded),
+    mRequestQueue(name, 1024 * 1024)
 {
+    llassert(threaded); // not threaded implementation is deprecated
+    mMainQueue = LL::WorkQueue::getInstance("mainloop");
+
 	if (mThreaded)
 	{
 		if(should_pause)
@@ -69,6 +75,11 @@ void LLQueuedThread::shutdown()
 	unpause(); // MAIN THREAD
 	if (mThreaded)
 	{
+        if (mRequestQueue.size() == 0)
+        {
+            mRequestQueue.close();
+        }
+
 		S32 timeout = 100;
 		for ( ; timeout>0; timeout--)
 		{
@@ -104,6 +115,8 @@ void LLQueuedThread::shutdown()
 	{
 		LL_WARNS() << "~LLQueuedThread() called with active requests: " << active_count << LL_ENDL;
 	}
+
+    mRequestQueue.close();
 }
 
 //----------------------------------------------------------------------------
@@ -112,6 +125,7 @@ void LLQueuedThread::shutdown()
 // virtual
 S32 LLQueuedThread::update(F32 max_time_ms)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	if (!mStarted)
 	{
 		if (!mThreaded)
@@ -125,29 +139,34 @@ S32 LLQueuedThread::update(F32 max_time_ms)
 
 S32 LLQueuedThread::updateQueue(F32 max_time_ms)
 {
-	F64 max_time = (F64)max_time_ms * .001;
-	LLTimer timer;
-	S32 pending = 1;
-
+    LL_PROFILE_ZONE_SCOPED;
 	// Frame Update
 	if (mThreaded)
 	{
-		pending = getPending();
-		if(pending > 0)
+        // schedule a call to threadedUpdate for every call to updateQueue
+        if (!isQuitting())
+        {
+            mRequestQueue.post([=]()
+                {
+                    LL_PROFILE_ZONE_NAMED_CATEGORY_THREAD("qt - update");
+                    mIdleThread = FALSE;
+                    threadedUpdate();
+                    mIdleThread = TRUE;
+                }
+            );
+        }
+
+		if(getPending() > 0)
 		{
-		unpause();
-	}
+		    unpause();
+	    }
 	}
 	else
 	{
-		while (pending > 0)
-		{
-			pending = processNextRequest();
-			if (max_time && timer.getElapsedTimeF64() > max_time)
-				break;
-		}
+        mRequestQueue.runFor(std::chrono::microseconds((int) (max_time_ms*1000.f)));
+        threadedUpdate();
 	}
-	return pending;
+	return getPending();
 }
 
 void LLQueuedThread::incQueue()
@@ -166,11 +185,7 @@ void LLQueuedThread::incQueue()
 // May be called from any thread
 S32 LLQueuedThread::getPending()
 {
-	S32 res;
-	lockData();
-	res = mRequestQueue.size();
-	unlockData();
-	return res;
+	return mRequestQueue.size();
 }
 
 // MAIN thread
@@ -195,35 +210,28 @@ void LLQueuedThread::waitOnPending()
 // MAIN thread
 void LLQueuedThread::printQueueStats()
 {
-	lockData();
-	if (!mRequestQueue.empty())
+    U32 size = mRequestQueue.size();
+	if (size > 0)
 	{
-		QueuedRequest *req = *mRequestQueue.begin();
-		LL_INFOS() << llformat("Pending Requests:%d Current status:%d", mRequestQueue.size(), req->getStatus()) << LL_ENDL;
+		LL_INFOS() << llformat("Pending Requests:%d ", mRequestQueue.size()) << LL_ENDL;
 	}
 	else
 	{
 		LL_INFOS() << "Queued Thread Idle" << LL_ENDL;
 	}
-	unlockData();
 }
 
 // MAIN thread
 LLQueuedThread::handle_t LLQueuedThread::generateHandle()
 {
-	lockData();
-	while ((mNextHandle == nullHandle()) || (mRequestHash.find(mNextHandle)))
-	{
-		mNextHandle++;
-	}
-	const LLQueuedThread::handle_t res = mNextHandle++;
-	unlockData();
+    U32 res = ++mNextHandle;
 	return res;
 }
 
 // MAIN thread
 bool LLQueuedThread::addRequest(QueuedRequest* req)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	if (mStatus == QUITTING)
 	{
 		return false;
@@ -231,14 +239,14 @@ bool LLQueuedThread::addRequest(QueuedRequest* req)
 	
 	lockData();
 	req->setStatus(STATUS_QUEUED);
-	mRequestQueue.insert(req);
-	mRequestHash.insert(req);
+    mRequestHash.insert(req);
 #if _DEBUG
 // 	LL_INFOS() << llformat("LLQueuedThread::Added req [%08d]",handle) << LL_ENDL;
 #endif
 	unlockData();
 
-	incQueue();
+    llassert(!mDataLock->isSelfLocked());
+    mRequestQueue.post([this, req]() { processRequest(req); });
 
 	return true;
 }
@@ -246,6 +254,7 @@ bool LLQueuedThread::addRequest(QueuedRequest* req)
 // MAIN thread
 bool LLQueuedThread::waitForResult(LLQueuedThread::handle_t handle, bool auto_complete)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	llassert (handle != nullHandle());
 	bool res = false;
 	bool waspaused = isPaused();
@@ -312,6 +321,7 @@ LLQueuedThread::status_t LLQueuedThread::getRequestStatus(handle_t handle)
 
 void LLQueuedThread::abortRequest(handle_t handle, bool autocomplete)
 {
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD;
 	lockData();
 	QueuedRequest* req = (QueuedRequest*)mRequestHash.find(handle);
 	if (req)
@@ -333,30 +343,9 @@ void LLQueuedThread::setFlags(handle_t handle, U32 flags)
 	unlockData();
 }
 
-void LLQueuedThread::setPriority(handle_t handle, U32 priority)
-{
-	lockData();
-	QueuedRequest* req = (QueuedRequest*)mRequestHash.find(handle);
-	if (req)
-	{
-		if(req->getStatus() == STATUS_INPROGRESS)
-		{
-			// not in list
-			req->setPriority(priority);
-		}
-		else if(req->getStatus() == STATUS_QUEUED)
-		{
-			// remove from list then re-insert
-			llverify(mRequestQueue.erase(req) == 1);
-			req->setPriority(priority);
-			mRequestQueue.insert(req);
-		}
-	}
-	unlockData();
-}
-
 bool LLQueuedThread::completeRequest(handle_t handle)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	bool res = false;
 	lockData();
 	QueuedRequest* req = (QueuedRequest*)mRequestHash.find(handle);
@@ -399,89 +388,115 @@ bool LLQueuedThread::check()
 //============================================================================
 // Runs on its OWN thread
 
-S32 LLQueuedThread::processNextRequest()
+void LLQueuedThread::processRequest(LLQueuedThread::QueuedRequest* req)
 {
-	QueuedRequest *req;
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD;
+
+    mIdleThread = FALSE;
+    //threadedUpdate();
+
 	// Get next request from pool
 	lockData();
 	
-	while(1)
+	if ((req->getFlags() & FLAG_ABORT) || (mStatus == QUITTING))
 	{
-		req = NULL;
-		if (mRequestQueue.empty())
+        LL_PROFILE_ZONE_NAMED_CATEGORY_THREAD("qtpr - abort");
+		req->setStatus(STATUS_ABORTED);
+		req->finishRequest(false);
+		if (req->getFlags() & FLAG_AUTO_COMPLETE)
 		{
-			break;
-		}
-		req = *mRequestQueue.begin();
-		mRequestQueue.erase(mRequestQueue.begin());
-		if ((req->getFlags() & FLAG_ABORT) || (mStatus == QUITTING))
-		{
-			req->setStatus(STATUS_ABORTED);
-			req->finishRequest(false);
-			if (req->getFlags() & FLAG_AUTO_COMPLETE)
-			{
-				mRequestHash.erase(req);
-				req->deleteRequest();
-// 				check();
-			}
-			continue;
-		}
-		llassert_always(req->getStatus() == STATUS_QUEUED);
-		break;
-	}
-	U32 start_priority = 0 ;
-	if (req)
-	{
-		req->setStatus(STATUS_INPROGRESS);
-		start_priority = req->getPriority();
-	}
-	unlockData();
-
-	// This is the only place we will call req->setStatus() after
-	// it has initially been seet to STATUS_QUEUED, so it is
-	// safe to access req.
-	if (req)
-	{
-		// process request		
-		bool complete = req->processRequest();
-
-		if (complete)
-		{
-			lockData();
-			req->setStatus(STATUS_COMPLETE);
-			req->finishRequest(true);
-			if (req->getFlags() & FLAG_AUTO_COMPLETE)
-			{
-				mRequestHash.erase(req);
-				req->deleteRequest();
+			mRequestHash.erase(req);
+			req->deleteRequest();
 // 				check();
-			}
-			unlockData();
 		}
-		else
-		{
-			lockData();
-			req->setStatus(STATUS_QUEUED);
-			mRequestQueue.insert(req);
-			unlockData();
-			if (mThreaded && start_priority < PRIORITY_NORMAL)
-			{
-				ms_sleep(1); // sleep the thread a little
-			}
-		}
-		
-		LLTrace::get_thread_recorder()->pushToParent();
+        unlockData();
 	}
+    else
+    {
+        llassert_always(req->getStatus() == STATUS_QUEUED);
+
+        if (req)
+        {
+            req->setStatus(STATUS_INPROGRESS);
+        }
+        unlockData();
+
+        // This is the only place we will call req->setStatus() after
+        // it has initially been seet to STATUS_QUEUED, so it is
+        // safe to access req.
+        if (req)
+        {
+            // process request		
+            bool complete = req->processRequest();
+
+            if (complete)
+            {
+                LL_PROFILE_ZONE_NAMED_CATEGORY_THREAD("qtpr - complete");
+                lockData();
+                req->setStatus(STATUS_COMPLETE);
+                req->finishRequest(true);
+                if (req->getFlags() & FLAG_AUTO_COMPLETE)
+                {
+                    mRequestHash.erase(req);
+                    req->deleteRequest();
+                    // 				check();
+                }
+                unlockData();
+            }
+            else
+            {
+                LL_PROFILE_ZONE_NAMED_CATEGORY_THREAD("qtpr - retry");
+                //put back on queue and try again in 0.1ms
+                lockData();
+                req->setStatus(STATUS_QUEUED);
+                
+                unlockData();
+
+                llassert(!mDataLock->isSelfLocked());
+
+#if 0
+                // try again on next frame
+                // NOTE: tried using "post" with a time in the future, but this
+                // would invariably cause this thread to wait for a long time (10+ ms)
+                // while work is pending
+                bool ret = LL::WorkQueue::postMaybe(
+                    mMainQueue,
+                    [=]()
+                    {
+                        LL_PROFILE_ZONE_NAMED("processRequest - retry");
+                        mRequestQueue.post([=]()
+                            {
+                                LL_PROFILE_ZONE_NAMED("processRequest - retry"); // <-- not redundant, track retry on both queues
+                                processRequest(req);
+                            });
+                    });
+                llassert(ret);
+#else
+                using namespace std::chrono_literals;
+                auto retry_time = LL::WorkQueue::TimePoint::clock::now() + 16ms;
+                mRequestQueue.post([=]
+                    {
+                        LL_PROFILE_ZONE_NAMED("processRequest - retry");
+                        while (LL::WorkQueue::TimePoint::clock::now() < retry_time)
+                        {
+                            std::this_thread::yield(); //note: don't use LLThread::yield here to avoid 
+                        }
+                        processRequest(req);
+                    });
+#endif
+                
+            }
+        }
+    }
 
-	S32 pending = getPending();
-	return pending;
+    mIdleThread = TRUE;
 }
 
 // virtual
 bool LLQueuedThread::runCondition()
 {
 	// mRunCondition must be locked here
-	if (mRequestQueue.empty() && mIdleThread)
+	if (mRequestQueue.size() == 0 && mIdleThread)
 		return false;
 	else
 		return true;
@@ -495,18 +510,13 @@ void LLQueuedThread::run()
 	startThread();
 	mStarted = TRUE;
 	
-	while (1)
+
+	/*while (1)
 	{
+        LL_PROFILE_ZONE_SCOPED;
 		// this will block on the condition until runCondition() returns true, the thread is unpaused, or the thread leaves the RUNNING state.
 		checkPause();
 		
-		if (isQuitting())
-		{
-			LLTrace::get_thread_recorder()->pushToParent();
-			endThread();
-			break;
-		}
-
 		mIdleThread = FALSE;
 
 		threadedUpdate();
@@ -515,12 +525,18 @@ void LLQueuedThread::run()
 
 		if (pending_work == 0)
 		{
+            //LL_PROFILE_ZONE_NAMED("LLQueuedThread - sleep");
 			mIdleThread = TRUE;
-			ms_sleep(1);
+			//ms_sleep(1);
 		}
 		//LLThread::yield(); // thread should yield after each request		
-	}
+	}*/
+    mRequestQueue.runUntilClose();
+
+    endThread();
 	LL_INFOS() << "LLQueuedThread " << mName << " EXITING." << LL_ENDL;
+
+    
 }
 
 // virtual
@@ -540,10 +556,9 @@ void LLQueuedThread::threadedUpdate()
 
 //============================================================================
 
-LLQueuedThread::QueuedRequest::QueuedRequest(LLQueuedThread::handle_t handle, U32 priority, U32 flags) :
+LLQueuedThread::QueuedRequest::QueuedRequest(LLQueuedThread::handle_t handle, U32 flags) :
 	LLSimpleHashEntry<LLQueuedThread::handle_t>(handle),
 	mStatus(STATUS_UNKNOWN),
-	mPriority(priority),
 	mFlags(flags)
 {
 }
diff --git a/indra/llcommon/llqueuedthread.h b/indra/llcommon/llqueuedthread.h
index 5d3f873646..6b82ccc434 100644
--- a/indra/llcommon/llqueuedthread.h
+++ b/indra/llcommon/llqueuedthread.h
@@ -36,6 +36,7 @@
 
 #include "llthread.h"
 #include "llsimplehash.h"
+#include "workqueue.h"
 
 //============================================================================
 // Note: ~LLQueuedThread is O(N) N=# of queued threads, assumed to be small
@@ -45,15 +46,6 @@ class LL_COMMON_API LLQueuedThread : public LLThread
 {
 	//------------------------------------------------------------------------
 public:
-	enum priority_t {
-		PRIORITY_IMMEDIATE = 0x7FFFFFFF,
-		PRIORITY_URGENT =    0x40000000,
-		PRIORITY_HIGH =      0x30000000,
-		PRIORITY_NORMAL =    0x20000000,
-		PRIORITY_LOW =       0x10000000,
-		PRIORITY_LOWBITS =   0x0FFFFFFF,
-		PRIORITY_HIGHBITS =  0x70000000
-	};
 	enum status_t {
 		STATUS_EXPIRED = -1,
 		STATUS_UNKNOWN = 0,
@@ -82,28 +74,17 @@ public:
 		virtual ~QueuedRequest(); // use deleteRequest()
 		
 	public:
-		QueuedRequest(handle_t handle, U32 priority, U32 flags = 0);
+		QueuedRequest(handle_t handle, U32 flags = 0);
 
 		status_t getStatus()
 		{
 			return mStatus;
 		}
-		U32 getPriority() const
-		{
-			return mPriority;
-		}
 		U32 getFlags() const
 		{
 			return mFlags;
 		}
-		bool higherPriority(const QueuedRequest& second) const
-		{
-			if ( mPriority == second.mPriority)
-				return mHashKey < second.mHashKey;
-			else
-				return mPriority > second.mPriority;
-		}
-
+		
 	protected:
 		status_t setStatus(status_t newstatus)
 		{
@@ -121,28 +102,11 @@ public:
 		virtual void finishRequest(bool completed); // Always called from thread after request has completed or aborted
 		virtual void deleteRequest(); // Only method to delete a request
 
-		void setPriority(U32 pri)
-		{
-			// Only do this on a request that is not in a queued list!
-			mPriority = pri;
-		};
-		
 	protected:
 		LLAtomicBase<status_t> mStatus;
-		U32 mPriority;
 		U32 mFlags;
 	};
 
-protected:
-	struct queued_request_less
-	{
-		bool operator()(const QueuedRequest* lhs, const QueuedRequest* rhs) const
-		{
-			return lhs->higherPriority(*rhs); // higher priority in front of queue (set)
-		}
-	};
-
-
 	//------------------------------------------------------------------------
 	
 public:
@@ -167,7 +131,7 @@ private:
 protected:
 	handle_t generateHandle();
 	bool addRequest(QueuedRequest* req);
-	S32  processNextRequest(void);
+	void processRequest(QueuedRequest* req);
 	void incQueue();
 
 public:
@@ -186,7 +150,6 @@ public:
 	status_t getRequestStatus(handle_t handle);
 	void abortRequest(handle_t handle, bool autocomplete);
 	void setFlags(handle_t handle, U32 flags);
-	void setPriority(handle_t handle, U32 priority);
 	bool completeRequest(handle_t handle);
 	// This is public for support classes like LLWorkerThread,
 	// but generally the methods above should be used.
@@ -200,8 +163,10 @@ protected:
 	BOOL mStarted;  // required when mThreaded is false to call startThread() from update()
 	LLAtomicBool mIdleThread; // request queue is empty (or we are quitting) and the thread is idle
 	
-	typedef std::set<QueuedRequest*, queued_request_less> request_queue_t;
-	request_queue_t mRequestQueue;
+	//typedef std::set<QueuedRequest*, queued_request_less> request_queue_t;
+	//request_queue_t mRequestQueue;
+    LL::WorkQueue mRequestQueue;
+    LL::WorkQueue::weak_t mMainQueue;
 
 	enum { REQUEST_HASH_SIZE = 512 }; // must be power of 2
 	typedef LLSimpleHash<handle_t, REQUEST_HASH_SIZE> request_hash_t;
diff --git a/indra/llcommon/llsys.cpp b/indra/llcommon/llsys.cpp
index 9b6bb3826c..45417bfa37 100644
--- a/indra/llcommon/llsys.cpp
+++ b/indra/llcommon/llsys.cpp
@@ -710,20 +710,28 @@ static U32Kilobytes LLMemoryAdjustKBResult(U32Kilobytes inKB)
 }
 #endif
 
+#if LL_DARWIN
+// static
+U32Kilobytes LLMemoryInfo::getHardwareMemSize()
+{
+    // This might work on Linux as well.  Someone check...
+    uint64_t phys = 0;
+    int mib[2] = { CTL_HW, HW_MEMSIZE };
+
+    size_t len = sizeof(phys);
+    sysctl(mib, 2, &phys, &len, NULL, 0);
+
+    return U64Bytes(phys);
+}
+#endif
+
 U32Kilobytes LLMemoryInfo::getPhysicalMemoryKB() const
 {
 #if LL_WINDOWS
 	return LLMemoryAdjustKBResult(U32Kilobytes(mStatsMap["Total Physical KB"].asInteger()));
 
 #elif LL_DARWIN
-	// This might work on Linux as well.  Someone check...
-	uint64_t phys = 0;
-	int mib[2] = { CTL_HW, HW_MEMSIZE };
-
-	size_t len = sizeof(phys);	
-	sysctl(mib, 2, &phys, &len, NULL, 0);
-	
-	return U64Bytes(phys);
+    return getHardwareMemSize();
 
 #elif LL_LINUX
 	U64 phys = 0;
diff --git a/indra/llcommon/llsys.h b/indra/llcommon/llsys.h
index cb92cb0ac6..538e61c521 100644
--- a/indra/llcommon/llsys.h
+++ b/indra/llcommon/llsys.h
@@ -117,7 +117,10 @@ public:
 	LLMemoryInfo(); ///< Default constructor
 	void stream(std::ostream& s) const;	///< output text info to s
 
-	U32Kilobytes getPhysicalMemoryKB() const; 
+	U32Kilobytes getPhysicalMemoryKB() const;
+#if LL_DARWIN
+    static U32Kilobytes getHardwareMemSize(); // Because some Mac linkers won't let us reference extern gSysMemory from a different lib.
+#endif
 
 	//get the available memory infomation in KiloBytes.
 	static void getAvailableMemoryKB(U32Kilobytes& avail_physical_mem_kb, U32Kilobytes& avail_virtual_mem_kb);
diff --git a/indra/llcommon/lltimer.cpp b/indra/llcommon/lltimer.cpp
index aaa6df325c..39dfee3755 100644
--- a/indra/llcommon/lltimer.cpp
+++ b/indra/llcommon/lltimer.cpp
@@ -30,6 +30,9 @@
 
 #include "u64.h"
 
+#include <chrono>
+#include <thread>
+
 #if LL_WINDOWS
 #	include "llwin32headerslean.h"
 #elif LL_LINUX || LL_DARWIN
@@ -64,7 +67,13 @@ LLTimer* LLTimer::sTimer = NULL;
 #if LL_WINDOWS
 void ms_sleep(U32 ms)
 {
-	Sleep(ms);
+    LL_PROFILE_ZONE_SCOPED;
+    using TimePoint = std::chrono::steady_clock::time_point;
+    auto resume_time = TimePoint::clock::now() + std::chrono::milliseconds(ms);
+    while (TimePoint::clock::now() < resume_time)
+    {
+        std::this_thread::yield(); //note: don't use LLThread::yield here to avoid yielding for too long
+    }
 }
 
 U32 micro_sleep(U64 us, U32 max_yields)
diff --git a/indra/llcommon/llworkerthread.cpp b/indra/llcommon/llworkerthread.cpp
index 4b91b2caca..02ce4823b8 100644
--- a/indra/llcommon/llworkerthread.cpp
+++ b/indra/llcommon/llworkerthread.cpp
@@ -133,11 +133,11 @@ S32 LLWorkerThread::update(F32 max_time_ms)
 
 //----------------------------------------------------------------------------
 
-LLWorkerThread::handle_t LLWorkerThread::addWorkRequest(LLWorkerClass* workerclass, S32 param, U32 priority)
+LLWorkerThread::handle_t LLWorkerThread::addWorkRequest(LLWorkerClass* workerclass, S32 param)
 {
 	handle_t handle = generateHandle();
 	
-	WorkRequest* req = new WorkRequest(handle, priority, workerclass, param);
+	WorkRequest* req = new WorkRequest(handle, workerclass, param);
 
 	bool res = addRequest(req);
 	if (!res)
@@ -160,8 +160,8 @@ void LLWorkerThread::deleteWorker(LLWorkerClass* workerclass)
 //============================================================================
 // Runs on its OWN thread
 
-LLWorkerThread::WorkRequest::WorkRequest(handle_t handle, U32 priority, LLWorkerClass* workerclass, S32 param) :
-	LLQueuedThread::QueuedRequest(handle, priority),
+LLWorkerThread::WorkRequest::WorkRequest(handle_t handle, LLWorkerClass* workerclass, S32 param) :
+	LLQueuedThread::QueuedRequest(handle),
 	mWorkerClass(workerclass),
 	mParam(param)
 {
@@ -180,6 +180,7 @@ void LLWorkerThread::WorkRequest::deleteRequest()
 // virtual
 bool LLWorkerThread::WorkRequest::processRequest()
 {
+    LL_PROFILE_ZONE_SCOPED;
 	LLWorkerClass* workerclass = getWorkerClass();
 	workerclass->setWorking(true);
 	bool complete = workerclass->doWork(getParam());
@@ -190,6 +191,7 @@ bool LLWorkerThread::WorkRequest::processRequest()
 // virtual
 void LLWorkerThread::WorkRequest::finishRequest(bool completed)
 {
+    LL_PROFILE_ZONE_SCOPED;
 	LLWorkerClass* workerclass = getWorkerClass();
 	workerclass->finishWork(getParam(), completed);
 	U32 flags = LLWorkerClass::WCF_WORK_FINISHED | (completed ? 0 : LLWorkerClass::WCF_WORK_ABORTED);
@@ -203,7 +205,6 @@ LLWorkerClass::LLWorkerClass(LLWorkerThread* workerthread, const std::string& na
 	: mWorkerThread(workerthread),
 	  mWorkerClassName(name),
 	  mRequestHandle(LLWorkerThread::nullHandle()),
-	  mRequestPriority(LLWorkerThread::PRIORITY_NORMAL),
 	  mMutex(),
 	  mWorkFlags(0)
 {
@@ -292,7 +293,7 @@ bool LLWorkerClass::yield()
 //----------------------------------------------------------------------------
 
 // calls startWork, adds doWork() to queue
-void LLWorkerClass::addWork(S32 param, U32 priority)
+void LLWorkerClass::addWork(S32 param)
 {
 	mMutex.lock();
 	llassert_always(!(mWorkFlags & (WCF_WORKING|WCF_HAVE_WORK)));
@@ -306,7 +307,7 @@ void LLWorkerClass::addWork(S32 param, U32 priority)
 	startWork(param);
 	clearFlags(WCF_WORK_FINISHED|WCF_WORK_ABORTED);
 	setFlags(WCF_HAVE_WORK);
-	mRequestHandle = mWorkerThread->addWorkRequest(this, param, priority);
+	mRequestHandle = mWorkerThread->addWorkRequest(this, param);
 	mMutex.unlock();
 }
 
@@ -321,7 +322,6 @@ void LLWorkerClass::abortWork(bool autocomplete)
 	if (mRequestHandle != LLWorkerThread::nullHandle())
 	{
 		mWorkerThread->abortRequest(mRequestHandle, autocomplete);
-		mWorkerThread->setPriority(mRequestHandle, LLQueuedThread::PRIORITY_IMMEDIATE);
 		setFlags(WCF_ABORT_REQUESTED);
 	}
 	mMutex.unlock();
@@ -395,16 +395,5 @@ void LLWorkerClass::scheduleDelete()
 	}
 }
 
-void LLWorkerClass::setPriority(U32 priority)
-{
-	mMutex.lock();
-	if (mRequestHandle != LLWorkerThread::nullHandle() && mRequestPriority != priority)
-	{
-		mRequestPriority = priority;
-		mWorkerThread->setPriority(mRequestHandle, priority);
-	}
-	mMutex.unlock();
-}
-
 //============================================================================
 
diff --git a/indra/llcommon/llworkerthread.h b/indra/llcommon/llworkerthread.h
index 0387e75c65..06bbb7369e 100644
--- a/indra/llcommon/llworkerthread.h
+++ b/indra/llcommon/llworkerthread.h
@@ -56,7 +56,7 @@ public:
 		virtual ~WorkRequest(); // use deleteRequest()
 		
 	public:
-		WorkRequest(handle_t handle, U32 priority, LLWorkerClass* workerclass, S32 param);
+		WorkRequest(handle_t handle, LLWorkerClass* workerclass, S32 param);
 
 		S32 getParam()
 		{
@@ -90,7 +90,7 @@ public:
 
 	/*virtual*/ S32 update(F32 max_time_ms);
 	
-	handle_t addWorkRequest(LLWorkerClass* workerclass, S32 param, U32 priority = PRIORITY_NORMAL);
+	handle_t addWorkRequest(LLWorkerClass* workerclass, S32 param);
 	
 	S32 getNumDeletes() { return (S32)mDeleteList.size(); } // debug
 
@@ -151,10 +151,6 @@ public:
 	bool isWorking() { return getFlags(WCF_WORKING); }
 	bool wasAborted() { return getFlags(WCF_ABORT_REQUESTED); }
 
-	// setPriority(): changes the priority of a request
-	void setPriority(U32 priority);
-	U32  getPriority() { return mRequestPriority; }
-		
 	const std::string& getName() const { return mWorkerClassName; }
 
 protected:
@@ -169,7 +165,7 @@ protected:
 	void setWorkerThread(LLWorkerThread* workerthread);
 
 	// addWork(): calls startWork, adds doWork() to queue
-	void addWork(S32 param, U32 priority = LLWorkerThread::PRIORITY_NORMAL);
+	void addWork(S32 param);
 
 	// abortWork(): requests that work be aborted
 	void abortWork(bool autocomplete);
@@ -193,7 +189,6 @@ protected:
 	LLWorkerThread* mWorkerThread;
 	std::string mWorkerClassName;
 	handle_t mRequestHandle;
-	U32 mRequestPriority; // last priority set
 
 private:
 	LLMutex mMutex;
diff --git a/indra/llcommon/threadpool.cpp b/indra/llcommon/threadpool.cpp
index ba914035e2..f49dd40a8b 100644
--- a/indra/llcommon/threadpool.cpp
+++ b/indra/llcommon/threadpool.cpp
@@ -17,14 +17,17 @@
 // std headers
 // external library headers
 // other Linden headers
+#include "commoncontrol.h"
 #include "llerror.h"
 #include "llevents.h"
+#include "llsd.h"
 #include "stringize.h"
 
 LL::ThreadPool::ThreadPool(const std::string& name, size_t threads, size_t capacity):
+    super(name),
     mQueue(name, capacity),
     mName("ThreadPool:" + name),
-    mThreadCount(threads)
+    mThreadCount(getConfiguredWidth(name, threads))
 {}
 
 void LL::ThreadPool::start()
@@ -86,3 +89,58 @@ void LL::ThreadPool::run()
 {
     mQueue.runUntilClose();
 }
+
+//static
+size_t LL::ThreadPool::getConfiguredWidth(const std::string& name, size_t dft)
+{
+    LLSD poolSizes;
+    try
+    {
+        poolSizes = LL::CommonControl::get("Global", "ThreadPoolSizes");
+        // "ThreadPoolSizes" is actually a map containing the sizes of
+        // interest -- or should be, if this process has an
+        // LLViewerControlListener instance and its settings include
+        // "ThreadPoolSizes". If we failed to retrieve it, perhaps we're in a
+        // program that doesn't define that, or perhaps there's no such
+        // setting, or perhaps we're asking too early, before the LLEventAPI
+        // itself has been instantiated. In any of those cases, it seems worth
+        // warning.
+        if (! poolSizes.isDefined())
+        {
+            // Note: we don't warn about absence of an override key for a
+            // particular ThreadPool name, that's fine. This warning is about
+            // complete absence of a ThreadPoolSizes setting, which we expect
+            // in a normal viewer session.
+            LL_WARNS("ThreadPool") << "No 'ThreadPoolSizes' setting for ThreadPool '"
+                                   << name << "'" << LL_ENDL;
+        }
+    }
+    catch (const LL::CommonControl::Error& exc)
+    {
+        // We don't want ThreadPool to *require* LLViewerControlListener.
+        // Just log it and carry on.
+        LL_WARNS("ThreadPool") << "Can't check 'ThreadPoolSizes': " << exc.what() << LL_ENDL;
+    }
+
+    LL_DEBUGS("ThreadPool") << "ThreadPoolSizes = " << poolSizes << LL_ENDL;
+    // LLSD treats an undefined value as an empty map when asked to retrieve a
+    // key, so we don't need this to be conditional.
+    LLSD sizeSpec{ poolSizes[name] };
+    // We retrieve sizeSpec as LLSD, rather than immediately as LLSD::Integer,
+    // so we can distinguish the case when it's undefined.
+    return sizeSpec.isInteger() ? sizeSpec.asInteger() : dft;
+}
+
+//static
+size_t LL::ThreadPool::getWidth(const std::string& name, size_t dft)
+{
+    auto instance{ getInstance(name) };
+    if (instance)
+    {
+        return instance->getWidth();
+    }
+    else
+    {
+        return getConfiguredWidth(name, dft);
+    }
+}
diff --git a/indra/llcommon/threadpool.h b/indra/llcommon/threadpool.h
index b79c9b9090..b49d511257 100644
--- a/indra/llcommon/threadpool.h
+++ b/indra/llcommon/threadpool.h
@@ -22,14 +22,25 @@
 namespace LL
 {
 
-    class ThreadPool
+    class ThreadPool: public LLInstanceTracker<ThreadPool, std::string>
     {
+    private:
+        using super = LLInstanceTracker<ThreadPool, std::string>;
     public:
         /**
          * Pass ThreadPool a string name. This can be used to look up the
          * relevant WorkQueue.
+         *
+         * The number of threads you pass sets the compile-time default. But
+         * if the user has overridden the LLSD map in the "ThreadPoolSizes"
+         * setting with a key matching this ThreadPool name, that setting
+         * overrides this parameter.
+         *
+         * Pass an explicit capacity to limit the size of the queue.
+         * Constraining the queue can cause a submitter to block. Do not
+         * constrain any ThreadPool accepting work from the main thread.
          */
-        ThreadPool(const std::string& name, size_t threads=1, size_t capacity=1024);
+        ThreadPool(const std::string& name, size_t threads=1, size_t capacity=1024*1024);
         virtual ~ThreadPool();
 
         /**
@@ -57,6 +68,25 @@ namespace LL
          */
         virtual void run();
 
+        /**
+         * getConfiguredWidth() returns the setting, if any, for the specified
+         * ThreadPool name. Returns dft if the "ThreadPoolSizes" map does not
+         * contain the specified name.
+         */
+        static
+        size_t getConfiguredWidth(const std::string& name, size_t dft=0);
+
+        /**
+         * This getWidth() returns the width of the instantiated ThreadPool
+         * with the specified name, if any. If no instance exists, returns its
+         * getConfiguredWidth() if any. If there's no instance and no relevant
+         * override, return dft. Presumably dft should match the threads
+         * parameter passed to the ThreadPool constructor call that will
+         * eventually instantiate the ThreadPool with that name.
+         */
+        static
+        size_t getWidth(const std::string& name, size_t dft);
+
     private:
         void run(const std::string& name);
 
diff --git a/indra/llcommon/workqueue.h b/indra/llcommon/workqueue.h
index 96574a18b9..784327f929 100644
--- a/indra/llcommon/workqueue.h
+++ b/indra/llcommon/workqueue.h
@@ -162,9 +162,15 @@ namespace LL
                        CALLABLE&& callable);
 
         template <typename CALLABLE>
+        bool tryPost(const TimePoint& time, CALLABLE&& callable)
+        {
+            return mQueue.tryPush(TimedWork(time, std::move(callable)));
+        }
+
+        template <typename CALLABLE>
         bool tryPost(CALLABLE&& callable)
         {
-            return mQueue.tryPush(TimedWork(TimePoint::clock::now(), std::move(callable)));
+            return mQueue.tryPush(TimePoint::clock::now(), std::move(callable));
         }
 
         /*------------------------- handshake API --------------------------*/