drain UDP socket to avoid dropped packets (#3565)

drain UDP socket in idleNetwork() to avoid dropped packets

3 files changed, 24 insertions, 53 deletions

diff --git a/indra/newview/llappviewer.cpp b/indra/newview/llappviewer.cpp
index 52bea875d9..ba474d3f39 100644
--- a/indra/newview/llappviewer.cpp
+++ b/indra/newview/llappviewer.cpp
@@ -350,8 +350,6 @@ LLVector3 gRelativeWindVec(0.0, 0.0, 0.0);
 
 U32 gPacketsIn = 0;
 
-bool gPrintMessagesThisFrame = false;
-
 bool gRandomizeFramerate = false;
 bool gPeriodicSlowFrame = false;
 
@@ -1495,9 +1493,9 @@ bool LLAppViewer::doFrame()
 
         {
             LL_PROFILE_ZONE_NAMED_CATEGORY_APP("df pauseMainloopTimeout");
-        pingMainloopTimeout("Main:Sleep");
+            pingMainloopTimeout("Main:Sleep");
 
-        pauseMainloopTimeout();
+            pauseMainloopTimeout();
         }
 
         // Sleep and run background threads
@@ -5217,12 +5215,9 @@ void LLAppViewer::idleNameCache()
 // Handle messages, and all message related stuff
 //
 
-#define TIME_THROTTLE_MESSAGES
 
-#ifdef TIME_THROTTLE_MESSAGES
-#define CHECK_MESSAGES_DEFAULT_MAX_TIME .020f // 50 ms = 50 fps (just for messages!)
+constexpr F32 CHECK_MESSAGES_DEFAULT_MAX_TIME = 0.020f; // 50 ms = 50 fps (just for messages!)
 static F32 CheckMessagesMaxTime = CHECK_MESSAGES_DEFAULT_MAX_TIME;
-#endif
 
 static LLTrace::BlockTimerStatHandle FTM_IDLE_NETWORK("Idle Network");
 static LLTrace::BlockTimerStatHandle FTM_MESSAGE_ACKS("Message Acks");
@@ -5249,6 +5244,7 @@ void LLAppViewer::idleNetwork()
         F32 total_time = 0.0f;
 
         {
+            bool needs_drain = false;
             LockMessageChecker lmc(gMessageSystem);
             while (lmc.checkAllMessages(frame_count, gServicePump))
             {
@@ -5265,50 +5261,41 @@ void LLAppViewer::idleNetwork()
 
                 if (total_decoded > MESSAGE_MAX_PER_FRAME)
                 {
+                    needs_drain = true;
                     break;
                 }
 
-#ifdef TIME_THROTTLE_MESSAGES
                 // Prevent slow packets from completely destroying the frame rate.
                 // This usually happens due to clumps of avatars taking huge amount
                 // of network processing time (which needs to be fixed, but this is
                 // a good limit anyway).
                 total_time = check_message_timer.getElapsedTimeF32();
                 if (total_time >= CheckMessagesMaxTime)
+                {
+                    needs_drain = true;
                     break;
-#endif
+                }
+            }
+            if (needs_drain || gMessageSystem->mPacketRing.getNumBufferedPackets() > 0)
+            {
+                // Rather than allow packets to silently backup on the socket
+                // we drain them into our own buffer so we know how many exist.
+                S32 num_buffered_packets = gMessageSystem->drainUdpSocket();
+                if (num_buffered_packets > 0)
+                {
+                    // Increase CheckMessagesMaxTime so that we will eventually catch up
+                    CheckMessagesMaxTime *= 1.035f; // 3.5% ~= 2x in 20 frames, ~8x in 60 frames
+                }
+            }
+            else
+            {
+                // Reset CheckMessagesMaxTime to default value
+                CheckMessagesMaxTime = CHECK_MESSAGES_DEFAULT_MAX_TIME;
             }
 
             // Handle per-frame message system processing.
             lmc.processAcks(gSavedSettings.getF32("AckCollectTime"));
         }
-
-#ifdef TIME_THROTTLE_MESSAGES
-        if (total_time >= CheckMessagesMaxTime)
-        {
-            // Increase CheckMessagesMaxTime so that we will eventually catch up
-            CheckMessagesMaxTime *= 1.035f; // 3.5% ~= x2 in 20 frames, ~8x in 60 frames
-        }
-        else
-        {
-            // Reset CheckMessagesMaxTime to default value
-            CheckMessagesMaxTime = CHECK_MESSAGES_DEFAULT_MAX_TIME;
-        }
-#endif
-
-        // Decode enqueued messages...
-        S32 remaining_possible_decodes = MESSAGE_MAX_PER_FRAME - total_decoded;
-
-        if( remaining_possible_decodes <= 0 )
-        {
-            LL_INFOS() << "Maxed out number of messages per frame at " << MESSAGE_MAX_PER_FRAME << LL_ENDL;
-        }
-
-        if (gPrintMessagesThisFrame)
-        {
-            LL_INFOS() << "Decoded " << total_decoded << " msgs this frame!" << LL_ENDL;
-            gPrintMessagesThisFrame = false;
-        }
     }
     add(LLStatViewer::NUM_NEW_OBJECTS, gObjectList.mNumNewObjects);
 
diff --git a/indra/newview/llappviewer.h b/indra/newview/llappviewer.h
index 4ce4259ed8..a253f06d14 100644
--- a/indra/newview/llappviewer.h
+++ b/indra/newview/llappviewer.h
@@ -400,7 +400,6 @@ extern std::string gLastVersionChannel;
 extern LLVector3 gWindVec;
 extern LLVector3 gRelativeWindVec;
 extern U32  gPacketsIn;
-extern bool gPrintMessagesThisFrame;
 
 extern bool gRandomizeFramerate;
 extern bool gPeriodicSlowFrame;
diff --git a/indra/newview/llstartup.cpp b/indra/newview/llstartup.cpp
index b32b80331a..5f6c5e1e15 100644
--- a/indra/newview/llstartup.cpp
+++ b/indra/newview/llstartup.cpp
@@ -623,21 +623,6 @@ bool idle_startup()
 
             F32 dropPercent = gSavedSettings.getF32("PacketDropPercentage");
             msg->mPacketRing.setDropPercentage(dropPercent);
-
-            F32 inBandwidth = gSavedSettings.getF32("InBandwidth");
-            F32 outBandwidth = gSavedSettings.getF32("OutBandwidth");
-            if (inBandwidth != 0.f)
-            {
-                LL_DEBUGS("AppInit") << "Setting packetring incoming bandwidth to " << inBandwidth << LL_ENDL;
-                msg->mPacketRing.setUseInThrottle(true);
-                msg->mPacketRing.setInBandwidth(inBandwidth);
-            }
-            if (outBandwidth != 0.f)
-            {
-                LL_DEBUGS("AppInit") << "Setting packetring outgoing bandwidth to " << outBandwidth << LL_ENDL;
-                msg->mPacketRing.setUseOutThrottle(true);
-                msg->mPacketRing.setOutBandwidth(outBandwidth);
-            }
         }
 
         LL_INFOS("AppInit") << "Message System Initialized." << LL_ENDL;