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我正在开发一个 wcf 应用程序，我开始看到一个奇怪的超时行为。我创建了一个与真实配置相同的 foo 应用程序，以确定问题是否与 wcf 相关。

客户端应用程序代码是这样的：

public class Clients
{
    public static void Main(string[] args)
    {
        var random = new Random();
        var run = true;
        var threads = 100;

        for (int i = 0; i < threads; i++)
        {
            int delay = random.Next(1000, 1500);

            var t = new Thread(() => {
                var id = Guid.NewGuid().ToString("N").Substring(0, 10);
                var client = new Client(@"client");

                while (run)
                {
                    Console.WriteLine(@"Sending thread id " + id);
                    client.Operation(@"Thread " + id);
                    Thread.Sleep(delay);
                }
            });
            t.Start();
        }
    }
}

服务器应用程序代码只记录发送到控制台的数据：

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple,
    InstanceContextMode = InstanceContextMode.Single,
    IncludeExceptionDetailInFaults = true,
    UseSynchronizationContext = false,
    ValidateMustUnderstand = false)]
public class Service : IService
{
    public void Operation(string data)
    {
        Console.WriteLine(@"Data received: {0}", data);
    }
}

这是 app.config 文件：

<?xml version="1.0"?>
<configuration>
<system.serviceModel>
<services>
  <service name="Test.Service" behaviorConfiguration="throttle">
    <endpoint name="service" 
              address="net.tcp://localhost/service" 
              binding="netTcpBinding" 
              bindingConfiguration="NetTcpBinding" 
              contract="Test.IService"/>
  </service>
</services>
<client>
  <endpoint name="client"
        address="net.tcp://localhost/service"
        binding="netTcpBinding" 
        bindingConfiguration="NetTcpBinding" 
        contract="Test.IService"/>
</client>
<bindings>
  <netTcpBinding>
    <binding name="NetTcpBinding"
             portSharingEnabled="true" 
             closeTimeout="00:01:00" 
             openTimeout="00:00:30" 
             receiveTimeout="00:00:10"
             sendTimeout="00:00:10"
             transactionFlow="false" 
             transferMode="Streamed" 
             transactionProtocol="OleTransactions"
             hostNameComparisonMode="StrongWildcard" 
             maxBufferPoolSize="6553600"
             maxBufferSize="6553600"
             maxConnections="500"
             maxReceivedMessageSize="6553600">
      <readerQuotas maxDepth="128" 
                    maxStringContentLength="3276800" 
                    maxArrayLength="6553600" 
                    maxBytesPerRead="1638400"
                    maxNameTableCharCount="6553600"/>
      <security mode="None">
        <transport protectionLevel="None"/>
      </security>
    </binding>
  </netTcpBinding>
</bindings>
<behaviors>
  <serviceBehaviors>
    <behavior name="throttle">
      <serviceThrottling maxConcurrentCalls="1000" 
                         maxConcurrentInstances="10"
                         maxConcurrentSessions="500"/>
    </behavior>
  </serviceBehaviors>
</behaviors>
</system.serviceModel>

如果同时运行两个应用程序并且客户端应用程序的线程数为 100，则一切正常。但是，如果我将线程数更改为 300，则会出现以下异常：

System.ServiceModel.CommunicationException: The socket connection was aborted. 
This could be caused by an error processing your message or a receive timeout 
being exceeded by the remote host, or an underlying network resource issue. 
Local socket timeout was '00:00:10'.---> System.Net.Sockets.SocketException: 
An existing connection was forcibly closed by the remote host at
System.ServiceModel.Channels.SocketConnection.ReadCore(Byte[] buffer, Int32 
offset, Int32 size, TimeSpan timeout, Boolean closing)

我在四核机器上使用端口共享，服务是自托管的。

这与我在实际应用程序中遇到的问题相同，但超时时间更长（2 分半钟）。我不敢相信 300 是具有 InstanceContextMode.Single 的服务可以处理的最大连接数。我阅读了有关默认 ChannelInitializationTimeout 值（设置为 5）的问题，但我认为这不是问题（在另一个测试中，我开始为所有线程创建并打开一个客户端，并等待 6 秒以启动所有线程）线程，结果是 10 秒后的相同异常）。也许我正在以错误的方式配置某些东西。

如果有人有线索或想法，他们会有所帮助。提前致谢。

更新

我将绑定从 netTcp 更改为 basicHttpBinding，现在一切正常（没有引发 CommunicationExceptions）。此外，我开始比以前更快地在服务中获取消息，有谁知道为什么我会通过 basicHttpBinding 获得这种改进？

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