Question

我正在开发一个ASP.NET MVC项目，并发现了几个未关闭的WCF服务连接，我认为这会导致TCP / IP端口耗尽。

我在资源监视器/网络/ TCP连接上检查了服务器，并且有数千个灰色连接作为＆＃34; IPV6 Loopback＆＃34;在某些时候，有很多连接，服务器停止响应服务端口。

存在一个依赖注入来处理控制器上的连接，并且有一个＆＃34; CloseChannel＆＃34;方法，但它没有调用，我对它做了一些更改，并开始在控制器上的Dipose方法中调用它来关闭连接，但我没有得到任何结果。环回继续出现。

我认为要做的两个解决方案是：

删除依赖注入并正常创建连接在每次使用时。

除了关闭连接之外，还要对服务器进行一些更改在此post

的疑问：有没有比我提议的更好的选择？如果没有，您认为哪一个最好？

谢谢大家！

PS：今天用于打开和关闭连接的代码：

在控制器上调用：

IClient wcfClient = WcfChannel.CreateChannel<IClient>(connectionstr, WcfChannel.WcfBinding.NetTcpBinding);

这是WcfChannel：

public static class WcfChannel
{
    public static T CreateChannel<T>(string endpointAddress, WcfBinding wcfBinding)
    {
        Binding binding = null;

        #region ReaderQuotas
        XmlDictionaryReaderQuotas readerQuotas = new XmlDictionaryReaderQuotas()
        {
            MaxDepth = int.MaxValue,
            MaxStringContentLength = int.MaxValue,
            MaxArrayLength = int.MaxValue,
            MaxBytesPerRead = int.MaxValue,
            MaxNameTableCharCount = int.MaxValue
        };
        #endregion

        switch (wcfBinding)
        {
            case WcfBinding.BasicHttpBinding:
            case WcfBinding.NetMsmqBinding:
            case WcfBinding.NetNamedPipeBinding:
                throw new NotImplementedException();

            case WcfBinding.NetTcpBinding:
                binding = new NetTcpBinding()
                {
                    Name = "NetTcpBinding",
                    MaxBufferPoolSize = long.MaxValue,
                    MaxBufferSize = int.MaxValue,
                    MaxReceivedMessageSize = int.MaxValue,
                    ReaderQuotas = readerQuotas,
                    Security = new NetTcpSecurity() { Mode = SecurityMode.None },
                    CloseTimeout = new TimeSpan(0, 5, 0),
                    OpenTimeout = new TimeSpan(0, 5, 0),
                    ReceiveTimeout = new TimeSpan(0, 5, 0),
                    SendTimeout = new TimeSpan(0, 5, 0)
                };
                break;

            case WcfBinding.NetTcpBindingStreamed:
                binding = new NetTcpBinding()
                {
                    Name = "NetTcpBindingStreamed",
                    TransferMode = TransferMode.Streamed,
                    MaxBufferPoolSize = long.MaxValue,
                    MaxBufferSize = int.MaxValue,
                    MaxReceivedMessageSize = int.MaxValue,
                    ReaderQuotas = readerQuotas,
                    Security = new NetTcpSecurity() { Mode = SecurityMode.None },
                    CloseTimeout = new TimeSpan(0, 5, 0),
                    OpenTimeout = new TimeSpan(0, 5, 0),
                    ReceiveTimeout = new TimeSpan(0, 5, 0),
                    SendTimeout = new TimeSpan(0, 5, 0)
                };
                break;
            case WcfBinding.WS2007HttpBinding:
            case WcfBinding.WSHttpBinding:
                throw new NotImplementedException();
            default:
                throw new NotImplementedException();
        }

        EndpointAddress endpoint = new EndpointAddress(endpointAddress);

        var channelFactory = new ChannelFactory<T>(binding, endpoint);
        T channelObj = channelFactory.CreateChannel();

        return channelObj;
    }

    public static void CloseChannel(this object obj)
    {
        if (obj != null)
        {
            try
            {
                (obj as IClientChannel).Close();
            }
            catch (CommunicationException)
            {
                if (obj.GetType().GetMethod("Abort") != null)
                {
                    (obj as IClientChannel).Abort();
                }
            }
            catch (TimeoutException)
            {
                if (obj.GetType().GetMethod("Abort") != null)
                {
                    (obj as IClientChannel).Abort();
                }
            }
            catch (Exception)
            {
                //many connections doesn't have and Abort or close
            }


            if (obj.GetType().GetMethod("Dispose") != null)
            {
                (obj as IDisposable).Dispose();
            }

            obj = null;
        }
    }

    public enum WcfBinding
    {
        BasicHttpBinding,
        NetMsmqBinding,
        NetNamedPipeBinding,
        NetTcpBinding,
        NetTcpBindingStreamed,
        WS2007HttpBinding,
        WSHttpBinding
    }
}

Answer 1

我怀疑您的问题是由于未管理WCF会话而产生的。 Net TCP绑定是基于会话的绑定，需要管理会话。与ASP.NET相比，会话由服务器启动和管理，在WCF中，会话由客户端启动和管理。您可以使用ServiceContract / SessionMode，OperationContract / IsInitiating / IsTerminating注释属性来管理会话。（此处的文档：https://docs.microsoft.com/en-us/dotnet/framework/wcf/using-sessions）

在客户端，您需要在结束会话后调用CloseChannel方法。此外，您需要验证所有异常的通道状态并调用abort方法（关于在此使用Net TCP绑定客户端的一些考虑因素：https://blogs.msdn.microsoft.com/rodneyviana/2016/02/29/considerations-for-nettcpbindingnetnamedpipebinding-you-may-not-be-aware/）。此外，在服务器端，作为最佳实践，可能需要启用服务限制以限制会话/服务实例（https://docs.microsoft.com/en-us/dotnet/framework/wcf/feature-details/using-servicethrottlingbehavior-to-control-wcf-service-performance）。

C＃Wcf连接导致TCP / IP端口耗尽

1 个答案: