public override byte[] TakeBuffer(int bufferSize)
{
InternalBufferManager.PooledBufferManager.BufferPool bufferPool = this.FindPool(bufferSize);
if (bufferPool == null)
{
if (TraceCore.BufferPoolAllocationIsEnabled(Fx.Trace))
{
TraceCore.BufferPoolAllocation(Fx.Trace, bufferSize);
}
return(Fx.AllocateByteArray(bufferSize));
}
byte[] array = bufferPool.Take();
if (array != null)
{
bufferPool.DecrementCount();
return(array);
}
if (bufferPool.Peak == bufferPool.Limit)
{
bufferPool.Misses++;
if (++this.totalMisses >= 8)
{
this.TuneQuotas();
}
}
if (TraceCore.BufferPoolAllocationIsEnabled(Fx.Trace))
{
TraceCore.BufferPoolAllocation(Fx.Trace, bufferPool.BufferSize);
}
return(Fx.AllocateByteArray(bufferPool.BufferSize));
}
public override void Clear()
{
for (int i = 0; i < this.bufferPools.Length; i++)
{
InternalBufferManager.PooledBufferManager.BufferPool bufferPool = this.bufferPools[i];
bufferPool.Clear();
}
}
private void TuneQuotas()
{
if (this.areQuotasBeingTuned)
{
return;
}
bool flag = false;
try
{
Monitor.TryEnter(this.tuningLock, ref flag);
if (!flag || this.areQuotasBeingTuned)
{
return;
}
this.areQuotasBeingTuned = true;
}
finally
{
if (flag)
{
Monitor.Exit(this.tuningLock);
}
}
int num = this.FindMostStarvedPool();
if (num >= 0)
{
InternalBufferManager.PooledBufferManager.BufferPool bufferPool = this.bufferPools[num];
if (this.remainingMemory < (long)bufferPool.BufferSize)
{
int num2 = this.FindMostExcessivePool();
if (num2 >= 0)
{
this.DecreaseQuota(ref this.bufferPools[num2]);
}
}
if (this.remainingMemory >= (long)bufferPool.BufferSize)
{
this.IncreaseQuota(ref this.bufferPools[num]);
}
}
for (int i = 0; i < this.bufferPools.Length; i++)
{
InternalBufferManager.PooledBufferManager.BufferPool bufferPool2 = this.bufferPools[i];
bufferPool2.Misses = 0;
}
this.totalMisses = 0;
this.areQuotasBeingTuned = false;
}
public override void ReturnBuffer(byte[] buffer)
{
InternalBufferManager.PooledBufferManager.BufferPool bufferPool = this.FindPool(buffer.Length);
if (bufferPool != null)
{
if (buffer.Length != bufferPool.BufferSize)
{
throw Fx.Exception.Argument("buffer", InternalSR.BufferIsNotRightSizeForBufferManager);
}
if (bufferPool.Return(buffer))
{
bufferPool.IncrementCount();
}
}
}
private int FindMostStarvedPool()
{
long num = 0L;
int result = -1;
for (int i = 0; i < this.bufferPools.Length; i++)
{
InternalBufferManager.PooledBufferManager.BufferPool bufferPool = this.bufferPools[i];
if (bufferPool.Peak == bufferPool.Limit)
{
long num2 = (long)bufferPool.Misses * (long)bufferPool.BufferSize;
if (num2 > num)
{
result = i;
num = num2;
}
}
}
return(result);
}
private void ChangeQuota(ref InternalBufferManager.PooledBufferManager.BufferPool bufferPool, int delta)
{
if (TraceCore.BufferPoolChangeQuotaIsEnabled(Fx.Trace))
{
TraceCore.BufferPoolChangeQuota(Fx.Trace, bufferPool.BufferSize, delta);
}
InternalBufferManager.PooledBufferManager.BufferPool bufferPool2 = bufferPool;
int num = bufferPool2.Limit + delta;
InternalBufferManager.PooledBufferManager.BufferPool bufferPool3 = InternalBufferManager.PooledBufferManager.BufferPool.CreatePool(bufferPool2.BufferSize, num);
for (int i = 0; i < num; i++)
{
byte[] array = bufferPool2.Take();
if (array == null)
{
break;
}
bufferPool3.Return(array);
bufferPool3.IncrementCount();
}
this.remainingMemory -= (long)(bufferPool2.BufferSize * delta);
bufferPool = bufferPool3;
}
private void IncreaseQuota(ref InternalBufferManager.PooledBufferManager.BufferPool bufferPool)
{
this.ChangeQuota(ref bufferPool, 1);
}