WCF调用时出现内存不足异常

Question

Our server is running in production environment, but after running for few days, out of memory exception occurs at WCF call.

Line 36007:    GlobalUnhandledException: System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
Line 36063:    at System.Net.Sockets.SocketAsyncEventArgs.FinishOperationSuccess(SocketError socketError, Int32 bytesTransferred, SocketFlags flags)
Line 36063:    at System.Net.Sockets.SocketAsyncEventArgs.FinishOperationSuccess(SocketError socketError, Int32 bytesTransferred, SocketFlags flags)
Line 36064:    at System.Net.Sockets.SocketAsyncEventArgs.CompletionPortCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped)
Line 36065:    at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)

We have try to give the maximum array size in configuration. Binding configuration of WCF at server side.

<netTcpBinding>
    <binding maxBufferSize="2147483647" maxReceivedMessageSize="2147483647" maxBufferPoolSize="524288" sendTimeout="00:00:35" transactionFlow="true"  >
      <reliableSession enabled="true" />
      <security mode="None" />
    </binding>
  </netTcpBinding>

Is there is memory leak issue happening at WCF connection calls?

Service behaviour:

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall,
                 ConcurrencyMode = ConcurrencyMode.Multiple,
                 ReleaseServiceInstanceOnTransactionComplete = false)]

Is there something I missed during configuration, what are steps to rectify or identify this out of memory exception any help on this matter is appreciated.

UPDATE: Operation contract:

[OperationContract]
    [TransactionFlow(TransactionFlowOption.Allowed)]

Answer 1

Yes, your configuration is the issue.

This is what your configuration means:

InstanceContextMode = InstanceContextMode.PerCall - Start a new service instance for each call made to the service.

ConcurrencyMode = ConcurrencyMode.Multiple - Allow multiple threads to start within the service instance

ReleaseServiceInstanceOnTransactionComplete = false - Do not release the service instance once the call is complete.

EDIT:

Based on your OperationContract for the method, I would specify the OperationBehaviour for the method and configure the Transaction completion behaviour according to your needs.

MSDN for ReleaseInstanceOnTransaction - has a good example of how OperationBehaviour should be configured to automatically complete the Transaction once the underlying operation has completed.

The underlying cause of your OutOfMemoryException is highly likely to be not completing Transactions and thus not causing the WCF ServiceInstance to be shutdown and garbage collected.