The remote host closed the connection. The error code is 0x800704CD.

[bladefist]

I have an application that can have anywhere from 1000 to 2000 active singalr connections, generally in a server sent events or longpolling state. Lately my app pool has been experiencing low cpu hangs and so I have been tracing the app and trying to determine what is hanging it up.

The most common exception I see during these hangs are the error in the title. I've done some research and saw that @davidfowl said these are quite normal and harmless. Are they? Are having thousands of these errors happening normal and harmless?

Using SignalR 2.2

ExceptionTrace attaching as a debugger, use CTRL-C to exit
System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:14492
System.Web.Hosting.IIS7WorkerRequest.RaiseCommunicationError(N/AN/AN/A)
System.Web.Hosting.IIS7WorkerRequest.ExplicitFlush(N/A)
System.Web.HttpResponse.Flush(System.Web.HttpResponseSystem.BooleanN/A)
System.Web.HttpWriter.WriteFromStream(N/AN/AN/AN/A)
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.PerformPartialSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:14492
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.PerformPartialSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:14492
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:14492
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:14492
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:7828
System.Web.Hosting.IIS7WorkerRequest.RaiseCommunicationError(N/AN/AN/A)
System.Web.Hosting.IIS7WorkerRequest.ExplicitFlush(N/A)
System.Web.HttpResponse.Flush(System.Web.HttpResponseSystem.BooleanN/A)
System.Web.HttpWriter.WriteFromStream(N/AN/AN/AN/A)
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.ServerSentEventsTransport.PerformSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.ForeverTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:7828
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.ServerSentEventsTransport.PerformSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.ForeverTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:7828
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:7828
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:7828
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:6556
System.Web.Hosting.IIS7WorkerRequest.RaiseCommunicationError(N/AN/AN/A)
System.Web.Hosting.IIS7WorkerRequest.ExplicitFlush(N/A)
System.Web.HttpResponse.Flush(System.Web.HttpResponseSystem.BooleanN/A)
System.Web.HttpWriter.WriteFromStream(N/AN/AN/AN/A)
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.PerformPartialSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:6556
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.PerformPartialSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.LongPollingTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:6556
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:6556
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:6556
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:5516
System.Web.Hosting.IIS7WorkerRequest.RaiseCommunicationError(N/AN/AN/A)
System.Web.Hosting.IIS7WorkerRequest.ExplicitFlush(N/A)
System.Web.HttpResponse.Flush(System.Web.HttpResponseSystem.BooleanN/A)
System.Web.HttpWriter.WriteFromStream(N/AN/AN/AN/A)
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.ServerSentEventsTransport.PerformSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.ForeverTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:5516
Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStream.Write(Microsoft.Owin.Host.SystemWeb.CallStreams.OutputStreamN/AN/AN/A)
Microsoft.AspNet.SignalR.Owin.ServerResponse.Write(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BinaryTextWriter.<.ctor>b__4(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter+ChunkedWriter.Flush(N/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.BufferTextWriter.Flush(N/A)
Microsoft.AspNet.SignalR.Transports.ServerSentEventsTransport.PerformSend(N/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.InvokeNext(N/AN/AN/A)
Microsoft.AspNet.SignalR.TaskAsyncHelper.FromMethod(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.TaskQueue.Enqueue(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.TransportDisconnectBase.EnqueueOperation(N/AN/AN/A)
Microsoft.AspNet.SignalR.Transports.ForeverTransport.OnMessageReceived(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection+ReceiveContext.InvokeCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.MessageBusCallback(N/AN/A)
Microsoft.AspNet.SignalR.Infrastructure.Connection.b__6(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:5516
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Invoke(N/AN/AN/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:5516
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.Subscription+d__8.MoveNext(Microsoft.AspNet.SignalR.Messaging.Subscription+d__8&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.Subscription.Work(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

System.Web.HttpException:"The remote host closed the connection. The error code is 0x800704CD."
OS Thread Id:5516
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(N/A)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(N/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2.MoveNext(Microsoft.AspNet.SignalR.Messaging.MessageBroker+d__2&)
System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start(N/AN/A)
Microsoft.AspNet.SignalR.Messaging.MessageBroker.b__0(N/A)
System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem(N/A)
System.Threading.ThreadPoolWorkQueue.Dispatch()

[aspnet-hello]

This issue has been closed as part of issue clean-up as described in https://blogs.msdn.microsoft.com/webdev/2018/09/17/the-future-of-asp-net-signalr/. If you're still encountering this problem, please feel free to re-open and comment to let us know! We're still interested in hearing from you, the backlog just got a little big and we had to do a bulk clean up to get back on top of things. Thanks for your continued feedback!