SH-4377 FIX: Interesting: Windows viewer crashes when SceneLoadingMonitorEnabled is enabled

indra/llcommon/lltraceaccumulators.cpp

@@ -145,7 +145,7 @@ void SampleAccumulator::addSamples( const SampleAccumulator& other, EBufferAppen
 
 		F64 epsilon = 0.0000001;
 
-		if (other.mTotalSamplingTime > epsilon)
+		if (other.mTotalSamplingTime > epsilon && mTotalSamplingTime > epsilon)
 		{
 			// combine variance (and hence standard deviation) of 2 different sized sample groups using
 			// the following formula: http://www.mrc-bsu.cam.ac.uk/cochrane/handbook/chapter_7/7_7_3_8_combining_groups.htm
@@ -173,7 +173,6 @@ void SampleAccumulator::addSamples( const SampleAccumulator& other, EBufferAppen
 			mNumSamples += other.mNumSamples;
 			mTotalSamplingTime += other.mTotalSamplingTime;
 			mMean = (mMean * weight) + (other.mMean * (1.0 - weight));
-			llassert(mMean < 0 || mMean >= 0);
 		}
 		if (append_type == SEQUENTIAL)
 		{

indra/llcommon/lltraceaccumulators.h

@@ -318,7 +318,6 @@ namespace LLTrace
 				mMin = value;
 				mMax = value;
 				mMean = value;
-				llassert(mMean < 0 || mMean >= 0);
 				mLastSampleTimeStamp = time_stamp;
 			}
 			else
@@ -336,15 +335,13 @@ namespace LLTrace
 
 		void sync(F64SecondsImplicit time_stamp)
 		{
-			if (mHasValue)
+			if (mHasValue && time_stamp != mLastSampleTimeStamp)
 			{
 				F64SecondsImplicit delta_time = time_stamp - mLastSampleTimeStamp;
 				mSum += mLastValue * delta_time;
 				mTotalSamplingTime += delta_time;
 				F64 old_mean = mMean;
-				llassert(mMean < 0 || mMean >= 0);
 				mMean += (delta_time / mTotalSamplingTime) * (mLastValue - old_mean);
-				llassert(mMean < 0 || mMean >= 0);
 				mSumOfSquares += delta_time * (mLastValue - old_mean) * (mLastValue - mMean);
 			}
 			mLastSampleTimeStamp = time_stamp;

indra/newview/llscenemonitor.cpp

@@ -283,6 +283,7 @@ void LLSceneMonitor::capture()
 		else
 		{
 			mEnabled = enabled;
+			reset();
 			freezeScene();
 		}
 	}