Question

至少一个星期以来，我一直在努力解决这个问题（也学到了新的东西--WCF是一个主要的PITA）。

这是我的问题：我的应用程序中有一个场景，在某些时候冻结整个客户端，例如，永远（因为我禁用了超时，因为客户端和服务器都在受控环境中）。死锁恰好发生在同一个呼叫中，我认为是由于它之前的请求突发。

检查客户端上的死锁堆栈跟踪给我这个：

[In a sleep, wait, or join] 
WindowsBase.dll!System.Windows.Threading.DispatcherSynchronizationContext.Wait(System.IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout) + 0x26 bytes 
mscorlib.dll!System.Threading.SynchronizationContext.InvokeWaitMethodHelper(System.Threading.SynchronizationContext syncContext, System.IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout) + 0x1c bytes   
[Native to Managed Transition]  
[Managed to Native Transition]  
mscorlib.dll!System.Threading.WaitHandle.InternalWaitOne(System.Runtime.InteropServices.SafeHandle waitableSafeHandle, long millisecondsTimeout, bool hasThreadAffinity, bool exitContext) + 0x2b bytes 
mscorlib.dll!System.Threading.WaitHandle.WaitOne(int millisecondsTimeout, bool exitContext) + 0x2d bytes    
mscorlib.dll!System.Threading.WaitHandle.WaitOne() + 0x10 bytes 
System.Runtime.DurableInstancing.dll!System.Runtime.TimeoutHelper.WaitOne(System.Threading.WaitHandle waitHandle, System.TimeSpan timeout) + 0x7c bytes 
System.ServiceModel.dll!System.ServiceModel.Channels.OverlappedContext.WaitForSyncOperation(System.TimeSpan timeout, ref object holder) + 0x40 bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.PipeConnection.WaitForSyncRead(System.TimeSpan timeout, bool traceExceptionsAsErrors) + 0x38 bytes 
System.ServiceModel.dll!System.ServiceModel.Channels.PipeConnection.Read(byte[] buffer, int offset, int size, System.TimeSpan timeout) + 0xef bytes 
System.ServiceModel.dll!System.ServiceModel.Channels.DelegatingConnection.Read(byte[] buffer, int offset, int size, System.TimeSpan timeout) + 0x21 bytes   
System.ServiceModel.dll!System.ServiceModel.Channels.ConnectionUpgradeHelper.InitiateUpgrade(System.ServiceModel.Channels.StreamUpgradeInitiator upgradeInitiator, ref System.ServiceModel.Channels.IConnection connection, System.ServiceModel.Channels.ClientFramingDecoder decoder, System.ServiceModel.IDefaultCommunicationTimeouts defaultTimeouts, ref System.Runtime.TimeoutHelper timeoutHelper) + 0xb3 bytes  
System.ServiceModel.dll!System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.SendPreamble(System.ServiceModel.Channels.IConnection connection, System.ArraySegment<byte> preamble, ref System.Runtime.TimeoutHelper timeoutHelper) + 0x155 bytes  
System.ServiceModel.dll!System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.DuplexConnectionPoolHelper.AcceptPooledConnection(System.ServiceModel.Channels.IConnection connection, ref System.Runtime.TimeoutHelper timeoutHelper) + 0x25 bytes  
System.ServiceModel.dll!System.ServiceModel.Channels.ConnectionPoolHelper.EstablishConnection(System.TimeSpan timeout) + 0xe2 bytes 
System.ServiceModel.dll!System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.OnOpen(System.TimeSpan timeout) + 0x37 bytes 
System.ServiceModel.dll!System.ServiceModel.Channels.CommunicationObject.Open(System.TimeSpan timeout) + 0x13f bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.ServiceChannel.OnOpen(System.TimeSpan timeout) + 0x52 bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.CommunicationObject.Open(System.TimeSpan timeout) + 0x13f bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.ServiceChannel.CallOpenOnce.System.ServiceModel.Channels.ServiceChannel.ICallOnce.Call(System.ServiceModel.Channels.ServiceChannel channel, System.TimeSpan timeout) + 0x12 bytes  
System.ServiceModel.dll!System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(System.TimeSpan timeout, System.ServiceModel.Channels.ServiceChannel.CallOnceManager cascade) + 0x10c bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.ServiceChannel.Call(string action, bool oneway, System.ServiceModel.Dispatcher.ProxyOperationRuntime operation, object[] ins, object[] outs, System.TimeSpan timeout) + 0x18b bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(System.Runtime.Remoting.Messaging.IMethodCallMessage methodCall, System.ServiceModel.Dispatcher.ProxyOperationRuntime operation) + 0x59 bytes    
System.ServiceModel.dll!System.ServiceModel.Channels.ServiceChannelProxy.Invoke(System.Runtime.Remoting.Messaging.IMessage message) + 0x65 bytes    
mscorlib.dll!System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(ref System.Runtime.Remoting.Proxies.MessageData msgData, int type) + 0xee bytes    
MyService.dll!MyService.Controller.CallMethod() + 0x9 bytes

我怀疑突发调用序列的原因是，如果我在调用之前插入60秒的睡眠，则不会发生死锁。

有人对如何避免此问题有任何建议吗？

P.S。我正在使用命名管道。

编辑：

客户端对WCF服务的调用发生在GUI线程上。我是否正确（从callstack）假设它试图访问导致死锁的GUI线程？

编辑：

客户端通道工厂初始化：

var binding = new NetNamedPipeBinding
    {
        OpenTimeout = TimeSpan.MaxValue,
        CloseTimeout = TimeSpan.MaxValue,
        SendTimeout = TimeSpan.MaxValue,
        ReceiveTimeout = TimeSpan.MaxValue,
        ReaderQuotas = { MaxStringContentLength = Int32.MaxValue, MaxArrayLength = Int32.MaxValue },
        MaxBufferPoolSize = Int32.MaxValue,
        MaxBufferSize = Int32.MaxValue,
        MaxReceivedMessageSize = Int32.MaxValue
    };
CustomBinding pipeBinding = new CustomBinding(binding);
pipeBinding.Elements.Find<NamedPipeTransportBindingElement>().ConnectionPoolSettings.IdleTimeout = TimeSpan.FromDays(24);
channelFactory = new ChannelFactory<ITestsModule>(pipeBinding,
    new EndpointAddress(string.Format("net.pipe://localhost/app_{0}/TestsModule", ProcessId)));

服务器端主机初始化：

var host = new ServiceHost(m_testModule, new Uri[] { new Uri(string.Format("net.pipe://localhost/app_{0}", Process.GetCurrentProcess().Id)) });
ServiceThrottlingBehavior throttle = host.Description.Behaviors.Find<ServiceThrottlingBehavior>();

if (throttle == null)
{
    throttle = new ServiceThrottlingBehavior();
    throttle.MaxConcurrentCalls = 500;
    throttle.MaxConcurrentSessions = 200;
    throttle.MaxConcurrentInstances = 100;
    host.Description.Behaviors.Add(throttle);
}

ThreadPool.SetMinThreads(1000, 1000);

var binding = new NetNamedPipeBinding
    {
        OpenTimeout = TimeSpan.MaxValue,
        CloseTimeout = TimeSpan.MaxValue,
        SendTimeout = TimeSpan.MaxValue,
        ReceiveTimeout = TimeSpan.MaxValue,
        ReaderQuotas = { MaxStringContentLength = Int32.MaxValue, MaxArrayLength = Int32.MaxValue },
        MaxBufferPoolSize = Int32.MaxValue,
        MaxBufferSize = Int32.MaxValue,
        MaxReceivedMessageSize = Int32.MaxValue
    };

CustomBinding pipeBinding = new CustomBinding(binding);
pipeBinding.Elements.Find<NamedPipeTransportBindingElement>().ConnectionPoolSettings.IdleTimeout = TimeSpan.FromDays(24);

host.AddServiceEndpoint(typeof(ITestsModule), pipeBinding, "TestsModule");

服务类行为：

[ServiceBehavior(
    InstanceContextMode = InstanceContextMode.Single,
    ConcurrencyMode = ConcurrencyMode.Multiple,
    UseSynchronizationContext = false,
    IncludeExceptionDetailInFaults = true
)]

Answer 1

首先，你知道你在服务器端锁定了什么吗？锁争用只来自WCF接口吗？或者您的服务器还从其他地方的其他组件/类锁定？这是最重要的问题，它与WCF无关。

现在，这说，试试这个来帮助缩小问题的范围：

选项1： 客户端超时 - 不要设置为Int32.MaxValue，设置为10秒，并在超时时实现客户端重试。

选项2：

ServiceThrottlingBehavior ThrottleBehavior = new ServiceThrottlingBehavior();
ThrottleBehavior.MaxConcurrentSessions = 4;
ThrottleBehavior.MaxConcurrentCalls = 4;
ThrottleBehavior.MaxConcurrentInstances = 4;

ServiceHost Host = ...
Host.Description.Behaviors.Add(ThrottleBehavior);

如果选项2有帮助，请对其进行压力测试（也应该与选项1相同） - 如果MaxConcurrentXXX设置为大数字，还要注意线程计数的累积。

希望这有帮助

当爆破请求时，客户端上的wcf死锁

1 个答案: