[TINKERPOP-2043] CloseAndRemoveAllConnections bubbles up System.Net.Http.WinHttpException and doesn't recover

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Duplicate
• Affects Version/s: 3.4.0
• Component/s: dotnet
• Environment: Gremlin.Net 3.4.0-rc1 ; Microsoft.NetCore.App v2.0
• Flags: Important
• Assignee: Unassigned
• Reporter: Sami
• Created: 20/Sep/18 21:41
• Updated: 11/Oct/18 15:32
• Resolved: 11/Oct/18 15:32

Description

We have a .Net Core web api with an Azure Cosmos db backend.

Our data access layer calls _gremlinConnection.Client.SubmitAsync<dynamic>(query) using a singleton gremlin connection. This has worked well except when the API is called with many parallel web api requests. The endpoints that we provide make around 5 gremlin calls (some to read, some to write cosmos db edges). 

During performance testing we noticed System.Net.Http.WinHttpException

Looking into the issue, we found that NrConnections was at 96 and the stack trace showed that Gremlin.Net called ConnectionPool.CloseAndRemoveAllConnections. 

We would expect that Gremlin.Net would recover after a call to CloseAndRemoveAllConnections and finish its "Client.SubmitAsync" call but instead it bubbles up the System.Net.Http.WinHttpException and immediately following calls to our API failed with the same System.Net.Http.WinHttpException.

 

Would you agree that Gremlin.Net's ConnectionPool.CloseAndRemoveAllConnections should recover on its own and complete its Client.SubmitAsync call or do you expect the consumer of Gremlin.Net to provide some work-around? If so, how can the pool be re-initiated or reset from outside of the Gremlin.Net library?

 

Here is the stack trace. Please note that we are ready for a release and this is holding us back. By the way, we do use Gremlin.Net 3.4 RC1 but 3.3.3 also proved to have the same issue.

 

// code placeholder
ProjectX.Exceptions.PersistenceFailedException:
at ProjectX.Repository.Cosmos.UnitOfWork+<DeletePersonAsync>d__32.MoveNext (<...removed...>)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at ProjectX.ModelAPI.Controllers.PersonsController+<RemovePerson>d__7.MoveNext (<...removed...>)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker+<InvokeActionMethodAsync>d__12.MoveNext (Microsoft.AspNetCore.Mvc.Core, Version=2.0.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker+<InvokeNextActionFilterAsync>d__10.MoveNext (Microsoft.AspNetCore.Mvc.Core, Version=2.0.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow (Microsoft.AspNetCore.Mvc.Core, Version=2.0.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next (Microsoft.AspNetCore.Mvc.Core, Version=2.0.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker+<InvokeInnerFilterAsync>d__14.MoveNext (Microsoft.AspNetCore.Mvc.Core, Version=2.0.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker+<InvokeNextExceptionFilterAsync>d__23.MoveNext (Microsoft.AspNetCore.Mvc.Core, Version=2.0.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60)
Inner exception System.Net.Http.WinHttpException handled at ProjectX.Repository.Cosmos.UnitOfWork+<DeletePersonAsync>d__32.MoveNext:
at System.Net.WebSockets.WinHttpWebSocket.InternalCloseAsync (System.Net.WebSockets.Client, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
at System.Net.WebSockets.WinHttpWebSocket+<CloseAsync>d__30.MoveNext (System.Net.WebSockets.Client, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Gremlin.Net.Driver.WebSocketConnection+<CloseAsync>d__4.MoveNext (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Gremlin.Net.Driver.Connection+<CloseAsync>d__10.MoveNext (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Gremlin.Net.Driver.ConnectionPool+<TeardownAsync>d__16.MoveNext (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Gremlin.Net.Process.Utils.WaitUnwrap (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at Gremlin.Net.Driver.ConnectionPool.CloseAndRemoveAllConnections (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at Gremlin.Net.Driver.ConnectionPool.AddConnectionIfOpen (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at Gremlin.Net.Driver.ProxyConnection.Dispose (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at Gremlin.Net.Driver.GremlinClient+<SubmitAsync>d__6`1.MoveNext (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at Gremlin.Net.Driver.GremlinClientExtensions+<SubmitAsync>d__4`1.MoveNext (Gremlin.Net, Version=3.4.0.0, Culture=neutral, PublicKeyToken=d2035e9aa387a711)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at ProjectX.Repository.Cosmos.Writer+<ExecuteGremlinCommand>d__7.MoveNext (<...removed...>)
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
at ProjectX.Repository.Cosmos.UnitOfWork+<DeletePersonAsync>d__32.MoveNext (<...removed...>)

Thank you so much for looking into this.

We're hoping for a reasonably quick fix or good work-around strategy.

Sami Abbushi

 

Issue Links

• duplicates: TINKERPOP-2026 Gremlin.Net.Driver should check ClientWebSocket.State before closing