WCF 客户端代理抛出 TimeoutException

Question

我的问题与 WCF 不时抛出的 System.TimeoutException 有关：

System.TimeoutException：打开 操作未在时间内完成 分配的超时为 00:00:00。时间 分配给该操作的可能有 是较长超时的一部分。 ---> System.TimeoutException：在 00:00:00 之后打开超时 建立传输会话 net.tcp://192.168.1.100:50000/TabletSvc/。 分配给此操作的时间 可能是更长的一部分 暂停。 --->系统超时异常： 连接到通过 net.tcp://192.168.1.100:50000/TabletSvc/ 00:00:00 后超时。联系 已尝试 0 次（共 1 次） 地址 ()。检查远程地址 您的频道并验证 该端点的 DNS 记录 对应于有效的 IP 地址。这 分配给该操作的时间可能 已经是更长的一部分 超时。

随机行为的可能原因是什么？

WCF 服务托管在 Windows XP SP2 上运行的 .NET 应用程序中。该应用程序为托管在不同计算机上的同一服务创建客户端代理。一个重要的方面是该服务正在使用可靠会话和服务限制。机器通过 WiFi 连接进行通信。

客户端和服务位于同一应用程序内的不同线程上。从这一点来看，他们并不相互依赖。不应该有锁定。

我使用 ping 检查了机器之间的 WiFi 连接，看起来没问题。下一步将是安装网络监视器，但由于它们是生产机器，因此可能不会很快发生。

我考虑过将 maxConcurrentSessions 和 maxConcurrentInstances 都增加到 50，但没有时间测试它。这是基于应用程序可能耗尽资源或达到影响托管服务的限制的想法。

正如我所说，客户端代理只是偶尔无法打开连接。一分钟后进行第二次尝试通常会成功。

这是客户端和服务配置：

<system.serviceModel>
<client>
  <endpoint name="TabletSvcEndpoint" address="net.tcp://localhost:50000/TabletSvc/" binding="netTcpBinding" bindingConfiguration="TabletSvcBinding" contract="ITabletSvc">
   <identity>
    <dns value="localhost" />
   </identity>
  </endpoint>
</client>

<services>
 <service behaviorConfiguration="TabletSvcBehavior" name="TabletSvc">
   <endpoint name="TabletSvcEndpoint" address="" binding="netTcpBinding" bindingConfiguration="TabletSvcBinding" contract="ITabletSvc">
    <identity>
     <dns value="localhost" />
    </identity>
   </endpoint>
   <host>
    <baseAddresses>
     <add baseAddress="net.tcp://localhost:50000/TabletSvc/" />
        </baseAddresses>
   </host>
 </service>
</services>

<bindings>
 <netTcpBinding>
   <binding name="TabletSvcBinding" receiveTimeout="00:30:00" sendTimeout="00:00:30" closeTimeout="00:00:05" openTimeout="00:00:05" transactionFlow="false" transferMode="Buffered" transactionProtocol="OleTransactions" hostNameComparisonMode="StrongWildcard" listenBacklog="10" maxBufferPoolSize="524288" maxBufferSize="6553600" maxConnections="10" maxReceivedMessageSize="6553600">
    <readerQuotas maxDepth="32" maxStringContentLength="819200" maxArrayLength="163840" maxBytesPerRead="4096" maxNameTableCharCount="16384" />
    <reliableSession inactivityTimeout="00:01:00" ordered="true" enabled="true" />
    <security mode="None" />
  </binding>
 </netTcpBinding>
</bindings>

<behaviors>
 <serviceBehaviors>
  <behavior name="TabletSvcBehavior">
   <serviceDebug includeExceptionDetailInFaults="true" />
   <serviceThrottling maxConcurrentSessions="10" maxConcurrentInstances="10" maxConcurrentCalls="100" />
  </behavior>
 </serviceBehaviors>
</behaviors>

<diagnostics performanceCounters="Off" wmiProviderEnabled="False" >
  <messageLogging maxMessagesToLog="250" logEntireMessage="true" logMessagesAtServiceLevel="true" logMalformedMessages="true" logMessagesAtTransportLevel="true" />
</diagnostics>
</system.serviceModel>

这是异常的堆栈跟踪：

10:20:18.3125 ClientChannel: Opening
10:20:48.8437 ClientChannel: Faulted
10:20:48.8593 Error: System.TimeoutException: The open operation did not complete within the allotted timeout of 00:00:00. The time allotted to this operation may have been a portion of a longer timeout. ---> System.TimeoutException: Open timed out after 00:00:00 while establishing a transport session to net.tcp://192.168.1.100:50000/TabletSvc/. The time allotted to this operation may have been a portion of a longer timeout. ---> System.TimeoutException: Connecting to via net.tcp://192.168.1.100:50000/TabletSvc/ timed out after 00:00:00. Connection attempts were made to 0 of 1 available addresses (). Check the RemoteAddress of your channel and verify that the DNS records for this endpoint correspond to valid IP Addresses. The time allotted to this operation may have been a portion of a longer timeout.
   at System.ServiceModel.Channels.SocketConnectionInitiator.CreateTimeoutException(Uri uri, TimeSpan timeout, IPAddress[] addresses, Int32 invalidAddressCount, SocketException innerException)
   at System.ServiceModel.Channels.SocketConnectionInitiator.Connect(Uri uri, TimeSpan timeout)
   at System.ServiceModel.Channels.BufferedConnectionInitiator.Connect(Uri uri, TimeSpan timeout)
   at System.ServiceModel.Channels.TracingConnectionInitiator.Connect(Uri uri, TimeSpan timeout)
   at System.ServiceModel.Channels.ConnectionPoolHelper.EstablishConnection(TimeSpan timeout)
   --- End of inner exception stack trace ---
   at System.ServiceModel.Channels.ConnectionPoolHelper.EstablishConnection(TimeSpan timeout)
   at System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.OnOpen(TimeSpan timeout)
   --- End of inner exception stack trace ---

Server stack trace: 
   at System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.ReliableChannelBinder`1.ChannelSynchronizer.SyncWaiter.TryGetChannel()
   at System.ServiceModel.Channels.ReliableChannelBinder`1.ChannelSynchronizer.SyncWaiter.TryWait(TChannel& channel)
   at System.ServiceModel.Channels.ReliableChannelBinder`1.ChannelSynchronizer.TryGetChannel(Boolean canGetChannel, Boolean canCauseFault, TimeSpan timeout, MaskingMode maskingMode, TChannel& channel)
   at System.ServiceModel.Channels.ReliableChannelBinder`1.Send(Message message, TimeSpan timeout, MaskingMode maskingMode)
   at System.ServiceModel.Channels.SendReceiveReliableRequestor.OnRequest(Message request, TimeSpan timeout, Boolean last)
   at System.ServiceModel.Channels.ReliableRequestor.Request(TimeSpan timeout)
   at System.ServiceModel.Channels.ClientReliableSession.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.ClientReliableDuplexSessionChannel.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.OnOpen(TimeSpan timeout)
   at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.CallOpenOnce.System.ServiceModel.Channels.ServiceChannel.ICallOnce.Call(ServiceChannel channel, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(TimeSpan timeout, CallOnceManager cascade)
   at System.ServiceModel.Channels.ServiceChannel.EnsureOpened(TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs)
   at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
   at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)

Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)

Answer 1

我也有这个问题。我已经通过用“127.0.0.1”替换“Localhost”解决了这个问题。

Answer 2

在 Windows XP SP2 上运行的 NET 应用程序

注意：对于 Windows XP Professional，允许通过网络同时连接的其他计算机的最大数量为 10 台。此限制包括所有传输和资源共享协议的组合。对于 Windows XP Home Edition，允许通过网络同时连接的其他计算机的最大数量为五台。

Microsoft KB

还将其添加到您的 app/web.config

<system.net>
   <connectionManagement>
     <add address="*" maxconnection="5000" />
   </connectionManagement>
</system.net> 

Microsoft 从来没有想过 XP 中的网络堆栈处理这么多连接...