C#和TCP客户端(Async)具有非常高的CPU负载和如何检测断开的客户端?

时间:2015-03-11 15:37:52

标签: c# tcp tcpclient tcplistener

如果多个客户端连接,则CPU负载为90+。 如果我启动监听器并且没有连接,一切都很棒。 如果我有一个或多个Connections,我的CPU负载非常高。

using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;

namespace Test.Socket
{
    public class Server
    {
        List<Thread> WorkListenerThread;

        TcpListener Listener;

        public Server()
        {
            WorkListenerThread = new List<Thread>();
        }

        public void Start()
        {
            try
            {
                Listener = new TcpListener(IPAddress.Any, 12345);
                Listener.Start();
                StartTCPClientListener();
            }
            catch (Exception) { }
        }

        private void StartTCPClientListener()
        {
            Listener.BeginAcceptTcpClient(new AsyncCallback(HandleTCPClientConnection), null);
        }

        private void HandleTCPClientConnection(IAsyncResult ar)
        {
            // Problem 1: after the first connection i have a high cpu load
            try
            {
                TcpClient client = Listener.EndAcceptTcpClient(ar);
                Thread clientThread = new Thread(Communicator.CreateConnection);
                clientThread.Start(client);
                WorkListenerThread.Add(clientThread);

                StartTCPClientListener(); // Next client
            }
            catch (Exception) { }
        }

        public void Stop()
        {
            foreach (Thread th in WorkListenerThread)
                if (th.IsAlive)
                    th.Abort();

            // Problem 2: Exception because the "HandleTCPClientConnection" get a wrong IAsyncResult
            if (Listener != null)
                Listener.Stop();
        }
    }
}

我的客户班。

using System;
using System.Collections.Generic;
using System.Net.Sockets;
using System.Text;
using JsonExSerializer;

namespace Test.Socket
{
    class Communicator
    {
        private TcpClient TcpClient = null;
        private NetworkStream Stream = null;

        private Communicator(TcpClient client)
        {
            TcpClient = client;
            Stream = TcpClient.GetStream();
            StartCommunication();
        }

        public static void CreateConnection(object c)
        {
            new Communicator(c as TcpClient);
        }

        private void StartCommunication()
        {
            string message; // The message
            int bytesRead; // Message length
            byte[] buffer = new byte[512]; // buffer

            while (true)
            {
                message = String.Empty;
                do
                {
                    bytesRead = Stream.Read(buffer, 0, buffer.Length);
                    message += Encoding.Default.GetString(buffer, 0, bytesRead);
                } while (!message.EndsWith("\r\n.\r\n"));

                Send("OK", Stream);
            }
        }

        protected void Send(string message, NetworkStream clientStream)
        {
            byte[] temp = Encoding.Default.GetBytes(message);
            clientStream.Write(temp, 0, temp.Length);
            clientStream.Flush();
        }
    }
}

我不知道什么是错的 - .-

有人知道如果客户端断开连接我怎么能检测到? 那也不错。

但是修复高CPU负载会非常好。

1 个答案:

答案 0 :(得分:6)

我猜这里的主要问题是:

while (true)
{
    message = String.Empty;
    do
    {
        bytesRead = Stream.Read(buffer, 0, buffer.Length);
        message += Encoding.Default.GetString(buffer, 0, bytesRead);
    } while (!message.EndsWith("\r\n.\r\n"));

    Send("OK", Stream);
}

您应该检查此bytesRead是否为非正数;如果是,那就是流的结束,你应该终止:永远不会有 ,但是你正处于一个紧密的循环中,永远地附加空字符串。

然而!更大的问题是这种方法:每个客户端的线程根本不会扩展,并且当人们提到“异步IO”时,他们的意思是什么。

我还会说,有一个构造函数启动一个长时间运行的操作(因此不返回)是一个可怕的事情。