Address PR feedback

Author: amcasey

src/Servers/Kestrel/Core/src/Internal/Http2/Http2Connection.cs

@@ -36,9 +36,22 @@ internal partial class Http2Connection : IHttp2StreamLifetimeHandler, IHttpHeade
  private const string EnhanceYourCalmMaximumCountProperty = "Microsoft.AspNetCore.Server.Kestrel.Http2.EnhanceYourCalmCount";
  private const string MaximumFlowControlQueueSizeProperty = "Microsoft.AspNetCore.Server.Kestrel.Http2.MaxConnectionFlowControlQueueSize";
 
- private static readonly int _enhanceYourCalmMaximumCount = AppContext.GetData(EnhanceYourCalmMaximumCountProperty) is int eycMaxCount
- ? eycMaxCount
- : 10;
+ private static readonly int _enhanceYourCalmMaximumCount = GetEnhanceYourCalmMaximumCount();
+
+ private static int GetEnhanceYourCalmMaximumCount()
+ {
+ var data = AppContext.GetData(EnhanceYourCalmMaximumCountProperty);
+ if (data is int count)
+ {
+ return count;
+ }
+ if (data is string countStr && int.TryParse(countStr, out var parsed))
+ {
+ return parsed;
+ }
+
+ return 20; // Empirically derived
+ }
 
  // Accumulate _enhanceYourCalmCount over the course of EnhanceYourCalmTickWindowCount ticks.
  // This should make bursts less likely to trigger disconnects.
@@ -176,10 +189,10 @@ public Http2Connection(HttpConnectionContext context)
  ? 4 * http2Limits.MaxStreamsPerConnection
  : (int)ConfiguredMaximumFlowControlQueueSize;
 
- if (_maximumFlowControlQueueSize < http2Limits.MaxStreamsPerConnection)
+ if (IsMaximumFlowControlQueueSizeEnabled && _maximumFlowControlQueueSize < http2Limits.MaxStreamsPerConnection)
  {
+ Log.Http2FlowControlQueueMaximumTooLow(context.ConnectionId, http2Limits.MaxStreamsPerConnection, _maximumFlowControlQueueSize);
  _maximumFlowControlQueueSize = http2Limits.MaxStreamsPerConnection;
- Log.LogTrace($"The configured maximum flow control queue size {ConfiguredMaximumFlowControlQueueSize} is less than the maximum streams per connection {http2Limits.MaxStreamsPerConnection} - increasing to match.");
  }
 
  // Start pool off at a smaller size if the max number of streams is less than the InitialStreamPoolSize

src/Servers/Kestrel/Core/src/Internal/Infrastructure/IKestrelTrace.cs

@@ -84,6 +84,8 @@ internal interface IKestrelTrace : ILogger
 
  void Http2FlowControlQueueOperationsExceeded(string connectionId, int count);
 
+ void Http2FlowControlQueueMaximumTooLow(string connectionId, int expected, int actual);
+
  void InvalidResponseHeaderRemoved();
 
  void Http3ConnectionError(string connectionId, Http3ConnectionErrorException ex);

src/Servers/Kestrel/Core/src/Internal/Infrastructure/KestrelTrace.cs

@@ -395,22 +395,30 @@ public void Http3GoAwayStreamId(string connectionId, long goAwayStreamId)
  Http3GoAwayStreamId(_http3Logger, connectionId, goAwayStreamId);
  }
 
- [LoggerMessage(54, LogLevel.Error, @"Connection id ""{ConnectionId}"" aborted since at least ""{Count}"" ENHANCE_YOUR_CALM responses were required per second.", EventName = "Http2TooManyEnhanceYourCalms")]
+ [LoggerMessage(54, LogLevel.Debug, @"Connection id ""{ConnectionId}"" aborted since at least ""{Count}"" ENHANCE_YOUR_CALM responses were required per second.", EventName = "Http2TooManyEnhanceYourCalms")]
  private static partial void Http2TooManyEnhanceYourCalms(ILogger logger, string connectionId, int count);
 
  public void Http2TooManyEnhanceYourCalms(string connectionId, int count)
  {
  Http2TooManyEnhanceYourCalms(_http2Logger, connectionId, count);
  }
 
- [LoggerMessage(55, LogLevel.Error, @"Connection id ""{ConnectionId}"" exceeded the output flow control maximum queue size of ""{Count}"".", EventName = "Http2FlowControlQueueOperationsExceeded")]
+ [LoggerMessage(55, LogLevel.Debug, @"Connection id ""{ConnectionId}"" exceeded the output flow control maximum queue size of ""{Count}"".", EventName = "Http2FlowControlQueueOperationsExceeded")]
  private static partial void Http2FlowControlQueueOperationsExceeded(ILogger logger, string connectionId, int count);
 
  public void Http2FlowControlQueueOperationsExceeded(string connectionId, int count)
  {
  Http2FlowControlQueueOperationsExceeded(_http3Logger, connectionId, count);
  }
 
+ [LoggerMessage(56, LogLevel.Debug, @"Connection id ""{ConnectionId}"" configured maximum flow control queue size ""{Actual}"" is less than the maximum streams per connection ""{Expected}"" - increasing to match.", EventName = "Http2FlowControlQueueMaximumTooLow")]
+ private static partial void Http2FlowControlQueueMaximumTooLow(ILogger logger, string connectionId, int expected, int actual);
+
+ public void Http2FlowControlQueueMaximumTooLow(string connectionId, int expected, int actual)
+ {
+ Http2FlowControlQueueMaximumTooLow(_http3Logger, connectionId, expected, actual);
+ }
+
  public virtual void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter)
  => _generalLogger.Log(logLevel, eventId, state, exception, formatter);
 

src/Servers/Kestrel/perf/Microbenchmarks/Mocks/MockTrace.cs

@@ -62,6 +62,7 @@ public void Http2FrameSending(string connectionId, Http2Frame frame) { }
  public void Http2TooManyEnhanceYourCalms(string connectionId, int count) { }
  public void Http2MaxConcurrentStreamsReached(string connectionId) { }
  public void Http2FlowControlQueueOperationsExceeded(string connectionId, int count) { }
+ public void Http2FlowControlQueueMaximumTooLow(string connectionId, int expected, int actual) { }
  public void InvalidResponseHeaderRemoved() { }
  public void Http3ConnectionError(string connectionId, Http3ConnectionErrorException ex) { }
  public void Http3ConnectionClosing(string connectionId) { }

src/Servers/Kestrel/shared/test/CompositeKestrelTrace.cs

@@ -252,6 +252,12 @@ public void Http2FlowControlQueueOperationsExceeded(string connectionId, int cou
  _trace2.Http2FlowControlQueueOperationsExceeded(connectionId, count);
  }
 
+ public void Http2FlowControlQueueMaximumTooLow(string connectionId, int expected, int actual)
+ {
+ _trace1.Http2FlowControlQueueMaximumTooLow(connectionId, expected, actual);
+ _trace2.Http2FlowControlQueueMaximumTooLow(connectionId, expected, actual);
+ }
+
  public void InvalidResponseHeaderRemoved()
  {
  _trace1.InvalidResponseHeaderRemoved();