#3644 Adjust throttle based of how busy buffer is

6 files changed, 23 insertions, 6 deletions

diff --git a/indra/llmessage/llpacketring.cpp b/indra/llmessage/llpacketring.cpp
index da3c502e9d..eb6650c6c5 100644
--- a/indra/llmessage/llpacketring.cpp
+++ b/indra/llmessage/llpacketring.cpp
@@ -344,6 +344,12 @@ bool LLPacketRing::expandRing()
     return true;
 }
 
+F32 LLPacketRing::getBufferLoadRate() const
+{
+    // goes up to MAX_BUFFER_RING_SIZE
+    return (F32)mNumBufferedPackets / (F32)DEFAULT_BUFFER_RING_SIZE;
+}
+
 void LLPacketRing::dumpPacketRingStats()
 {
     mNumDroppedPacketsTotal += mNumDroppedPackets;
diff --git a/indra/llmessage/llpacketring.h b/indra/llmessage/llpacketring.h
index 237efc12e0..572dcbd271 100644
--- a/indra/llmessage/llpacketring.h
+++ b/indra/llmessage/llpacketring.h
@@ -64,6 +64,7 @@ public:
     S32 getNumBufferedBytes() const { return mNumBufferedBytes; }
     S32 getNumDroppedPackets() const { return mNumDroppedPacketsTotal + mNumDroppedPackets; }
 
+    F32 getBufferLoadRate() const; // from 0 to 4 (0 - empty, 1 - default size is full)
     void dumpPacketRingStats();
 protected:
     // returns 'true' if we should intentionally drop a packet
diff --git a/indra/llmessage/message.h b/indra/llmessage/message.h
index 1844d5e7cd..30945cac51 100644
--- a/indra/llmessage/message.h
+++ b/indra/llmessage/message.h
@@ -538,7 +538,6 @@ public:
 
     //void  buildMessage();
 
-    S32     zeroCode(U8 **data, S32 *data_size);
     S32     zeroCodeExpand(U8 **data, S32 *data_size);
     S32     zeroCodeAdjustCurrentSendTotal();
 
@@ -755,6 +754,7 @@ public:
     S32     getReceiveBytes() const;
 
     S32     getUnackedListSize() const          { return mUnackedListSize; }
+    F32     getBufferLoadRate() const           { return mPacketRing.getBufferLoadRate(); }
 
     //const char* getCurrentSMessageName() const { return mCurrentSMessageName; }
     //const char* getCurrentSBlockName() const { return mCurrentSBlockName; }
@@ -842,12 +842,10 @@ private:
     LLUUID mSessionID;
 
     void    addTemplate(LLMessageTemplate *templatep);
-    bool        decodeTemplate( const U8* buffer, S32 buffer_size, LLMessageTemplate** msg_template );
 
     void        logMsgFromInvalidCircuit( const LLHost& sender, bool recv_reliable );
     void        logTrustedMsgFromUntrustedCircuit( const LLHost& sender );
     void        logValidMsg(LLCircuitData *cdp, const LLHost& sender, bool recv_reliable, bool recv_resent, bool recv_acks );
-    void        logRanOffEndOfPacket( const LLHost& sender );
 
     class LLMessageCountInfo
     {
diff --git a/indra/newview/llappviewer.cpp b/indra/newview/llappviewer.cpp
index a05c2376a0..4cf651de33 100644
--- a/indra/newview/llappviewer.cpp
+++ b/indra/newview/llappviewer.cpp
@@ -5443,6 +5443,7 @@ void LLAppViewer::idleNetwork()
     // Retransmit unacknowledged packets.
     gXferManager->retransmitUnackedPackets();
     gAssetStorage->checkForTimeouts();
+    gViewerThrottle.setBufferLoadRate(gMessageSystem->getBufferLoadRate());
     gViewerThrottle.updateDynamicThrottle();
 
     // Check that the circuit between the viewer and the agent's current
diff --git a/indra/newview/llviewerthrottle.cpp b/indra/newview/llviewerthrottle.cpp
index b0a00c29a4..8d935e4243 100644
--- a/indra/newview/llviewerthrottle.cpp
+++ b/indra/newview/llviewerthrottle.cpp
@@ -48,6 +48,8 @@ const F32 MIN_FRACTIONAL = 0.2f;
 const F32 MIN_BANDWIDTH = 50.f;
 const F32 MAX_BANDWIDTH = 6000.f;
 const F32 STEP_FRACTIONAL = 0.1f;
+const F32 HIGH_BUFFER_LOAD_TRESHOLD = 1.f;
+const F32 LOW_BUFFER_LOAD_TRESHOLD = 0.8f;
 const LLUnit<F32, LLUnits::Percent> TIGHTEN_THROTTLE_THRESHOLD(3.0f); // packet loss % per s
 const LLUnit<F32, LLUnits::Percent> EASE_THROTTLE_THRESHOLD(0.5f); // packet loss % per s
 const F32 DYNAMIC_UPDATE_DURATION = 5.0f; // seconds
@@ -146,7 +148,7 @@ LLViewerThrottleGroup LLViewerThrottleGroup::operator-(const LLViewerThrottleGro
 
 void LLViewerThrottleGroup::sendToSim() const
 {
-    LL_INFOS() << "Sending throttle settings, total BW " << mThrottleTotal << LL_ENDL;
+    LL_DEBUGS("Throttle") << "Sending throttle settings, total BW " << mThrottleTotal << LL_ENDL;
     LLMessageSystem* msg = gMessageSystem;
 
     msg->newMessageFast(_PREHASH_AgentThrottle);
@@ -305,7 +307,10 @@ void LLViewerThrottle::updateDynamicThrottle()
     mUpdateTimer.reset();
 
     LLUnit<F32, LLUnits::Percent> mean_packets_lost = LLViewerStats::instance().getRecording().getMean(LLStatViewer::PACKETS_LOST_PERCENT);
-    if (mean_packets_lost > TIGHTEN_THROTTLE_THRESHOLD)
+    if (
+        mean_packets_lost > TIGHTEN_THROTTLE_THRESHOLD // already losing packets
+        || mBufferLoadRate >= HIGH_BUFFER_LOAD_TRESHOLD // let viewer sort through the backlog before it starts dropping packets
+        )
     {
         if (mThrottleFrac <= MIN_FRACTIONAL || mCurrentBandwidth / 1024.0f <= MIN_BANDWIDTH)
         {
@@ -318,7 +323,8 @@ void LLViewerThrottle::updateDynamicThrottle()
         mCurrent.sendToSim();
         LL_INFOS() << "Tightening network throttle to " << mCurrentBandwidth << LL_ENDL;
     }
-    else if (mean_packets_lost <= EASE_THROTTLE_THRESHOLD)
+    else if (mean_packets_lost <= EASE_THROTTLE_THRESHOLD
+             && mBufferLoadRate < LOW_BUFFER_LOAD_TRESHOLD)
     {
         if (mThrottleFrac >= MAX_FRACTIONAL || mCurrentBandwidth / 1024.0f >= MAX_BANDWIDTH)
         {
@@ -331,4 +337,6 @@ void LLViewerThrottle::updateDynamicThrottle()
         mCurrent.sendToSim();
         LL_INFOS() << "Easing network throttle to " << mCurrentBandwidth << LL_ENDL;
     }
+
+    mBufferLoadRate = 0;
 }
diff --git a/indra/newview/llviewerthrottle.h b/indra/newview/llviewerthrottle.h
index 28a24d04fc..9973c88549 100644
--- a/indra/newview/llviewerthrottle.h
+++ b/indra/newview/llviewerthrottle.h
@@ -70,12 +70,15 @@ public:
     void updateDynamicThrottle();
     void resetDynamicThrottle();
 
+    void setBufferLoadRate(F32 rate) { mBufferLoadRate = llmax(mBufferLoadRate, rate); }
+
     LLViewerThrottleGroup getThrottleGroup(const F32 bandwidth_kbps);
 
     static const std::string sNames[TC_EOF];
 protected:
     F32 mMaxBandwidth;
     F32 mCurrentBandwidth;
+    F32 mBufferLoadRate = 0;
 
     LLViewerThrottleGroup mCurrent;