轉 C#高性能Socket服務器SocketAsyncEventArgs的實現(IOCP)

原創性申明

本文做者:小竹zz  博客地址:http://blog.csdn.net/zhujunxxxxx/article/details/43573879轉載請註明出處
引言

我一直在探尋一個高性能的Socket客戶端代碼。之前，我使用Socket類寫了一些基於傳統異步編程模型的代碼（BeginSend、BeginReceive，等等）也看過不少博客的知識，在linux中有poll和epoll來實現，在windows下面
微軟MSDN中也提供了SocketAsyncEventArgs這個類來實現IOCP 地址:https://msdn.microsoft.com/zh-cn/library/system.net.sockets.socketasynceventargs.aspx
NET Framework中的APM也稱爲Begin/End模式。這是由於會調用Begin方法來啓動異步操做，而後返回一個IAsyncResult 對象。能夠選擇將一個代理做爲參數提供給Begin方法，異步操做完成時會調用該方法。或者，一個線程能夠等待 IAsyncResult.AsyncWaitHandle。當回調被調用或發出等待信號時，就會調用End方法來獲取異步操做的結果。這種模式很靈活，使用相對簡單，在 .NET Framework 中很是常見。
可是，您必須注意，若是進行大量異步套接字操做，是要付出代價的。針對每次操做，都必須建立一個IAsyncResult對象，並且該對象不能被重複使用。因爲大量使用對象分配和垃圾收集，這會影響性能。爲了解決這個問題，新版本提供了另外一個使用套接字上執行異步I/O的方法模式。這種新模式並不要求爲每一個套接字操做分配操做上下文對象。

代碼下載：http://download.csdn.net/detail/zhujunxxxxx/8431289 這裏的代碼優化了的
目標

在上面微軟提供的例子我以爲不是很完整，沒有具體一個流程，只是受到客戶端消息後發送相同內容給客戶端，初學者不容易看懂流程，由於我花了一天的時間來實現一個功能齊全的IOCP服務器，

效果以下

 

代碼

首先是ICOPServer.cs 這個類是IOCP服務器的核心類，目前這個類是網絡上比較全的代碼，MSDN上面的例子都沒有個人全

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

namespace ServerTest
{
/// <summary>
/// IOCP SOCKET服務器
/// </summary>
public class IOCPServer : IDisposable
{
const int opsToPreAlloc = 2;
#region Fields
/// <summary>
/// 服務器程序容許的最大客戶端鏈接數
/// </summary>
private int _maxClient;

/// <summary>
/// 監聽Socket，用於接受客戶端的鏈接請求
/// </summary>
private Socket _serverSock;

/// <summary>
/// 當前的鏈接的客戶端數
/// </summary>
private int _clientCount;

/// <summary>
/// 用於每一個I/O Socket操做的緩衝區大小
/// </summary>
private int _bufferSize = 1024;

/// <summary>
/// 信號量
/// </summary>
Semaphore _maxAcceptedClients;

/// <summary>
/// 緩衝區管理
/// </summary>
BufferManager _bufferManager;

/// <summary>
/// 對象池
/// </summary>
SocketAsyncEventArgsPool _objectPool;

private bool disposed = false;

#endregion

#region Properties

/// <summary>
/// 服務器是否正在運行
/// </summary>
public bool IsRunning { get; private set; }
/// <summary>
/// 監聽的IP地址
/// </summary>
public IPAddress Address { get; private set; }
/// <summary>
/// 監聽的端口
/// </summary>
public int Port { get; private set; }
/// <summary>
/// 通訊使用的編碼
/// </summary>
public Encoding Encoding { get; set; }

#endregion

#region Ctors

/// <summary>
/// 異步IOCP SOCKET服務器
/// </summary>
/// <param name="listenPort">監聽的端口</param>
/// <param name="maxClient">最大的客戶端數量</param>
public IOCPServer(int listenPort,int maxClient)
: this(IPAddress.Any, listenPort, maxClient)
{
}

/// <summary>
/// 異步Socket TCP服務器
/// </summary>
/// <param name="localEP">監聽的終結點</param>
/// <param name="maxClient">最大客戶端數量</param>
public IOCPServer(IPEndPoint localEP, int maxClient)
: this(localEP.Address, localEP.Port,maxClient)
{
}

/// <summary>
/// 異步Socket TCP服務器
/// </summary>
/// <param name="localIPAddress">監聽的IP地址</param>
/// <param name="listenPort">監聽的端口</param>
/// <param name="maxClient">最大客戶端數量</param>
public IOCPServer(IPAddress localIPAddress, int listenPort, int maxClient)
{
this.Address = localIPAddress;
this.Port = listenPort;
this.Encoding = Encoding.Default;

_maxClient = maxClient;

_serverSock = new Socket(localIPAddress.AddressFamily, SocketType.Stream, ProtocolType.Tcp);

_bufferManager = new BufferManager(_bufferSize * _maxClient * opsToPreAlloc,_bufferSize);

_objectPool = new SocketAsyncEventArgsPool(_maxClient);

_maxAcceptedClients = new Semaphore(_maxClient, _maxClient);
}

#endregion


#region 初始化

/// <summary>
/// 初始化函數
/// </summary>
public void Init()
{
// Allocates one large byte buffer which all I/O operations use a piece of. This gaurds
// against memory fragmentation
_bufferManager.InitBuffer();

// preallocate pool of SocketAsyncEventArgs objects
SocketAsyncEventArgs readWriteEventArg;

for (int i = 0; i < _maxClient; i++)
{
//Pre-allocate a set of reusable SocketAsyncEventArgs
readWriteEventArg = new SocketAsyncEventArgs();
readWriteEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(OnIOCompleted);
readWriteEventArg.UserToken = null;

// assign a byte buffer from the buffer pool to the SocketAsyncEventArg object
_bufferManager.SetBuffer(readWriteEventArg);

// add SocketAsyncEventArg to the pool
_objectPool.Push(readWriteEventArg);
}

}

#endregion

#region Start
/// <summary>
/// 啓動
/// </summary>
public void Start()
{
if (!IsRunning)
{
Init();
IsRunning = true;
IPEndPoint localEndPoint = new IPEndPoint(Address, Port);
// 建立監聽socket
_serverSock = new Socket(localEndPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
//_serverSock.ReceiveBufferSize = _bufferSize;
//_serverSock.SendBufferSize = _bufferSize;
if (localEndPoint.AddressFamily == AddressFamily.InterNetworkV6)
{
// 配置監聽socket爲 dual-mode (IPv4 & IPv6)
// 27 is equivalent to IPV6_V6ONLY socket option in the winsock snippet below,
_serverSock.SetSocketOption(SocketOptionLevel.IPv6, (SocketOptionName)27, false);
_serverSock.Bind(new IPEndPoint(IPAddress.IPv6Any, localEndPoint.Port));
}
else
{
_serverSock.Bind(localEndPoint);
}
// 開始監聽
_serverSock.Listen(this._maxClient);
// 在監聽Socket上投遞一個接受請求。
StartAccept(null);
}
}
#endregion

#region Stop

/// <summary>
/// 中止服務
/// </summary>
public void Stop()
{
if (IsRunning)
{
IsRunning = false;
_serverSock.Close();
//TODO 關閉對全部客戶端的鏈接

}
}

#endregion


#region Accept

/// <summary>
/// 從客戶端開始接受一個鏈接操做
/// </summary>
private void StartAccept(SocketAsyncEventArgs asyniar)
{
if (asyniar == null)
{
asyniar = new SocketAsyncEventArgs();
asyniar.Completed += new EventHandler<SocketAsyncEventArgs>(OnAcceptCompleted);
}
else
{
//socket must be cleared since the context object is being reused
asyniar.AcceptSocket = null;
}
_maxAcceptedClients.WaitOne();
if (!_serverSock.AcceptAsync(asyniar))
{
ProcessAccept(asyniar);
//若是I/O掛起等待異步則觸發AcceptAsyn_Asyn_Completed事件
//此時I/O操做同步完成，不會觸發Asyn_Completed事件，因此指定BeginAccept()方法
}
}

/// <summary>
/// accept 操做完成時回調函數
/// </summary>
/// <param name="sender">Object who raised the event.</param>
/// <param name="e">SocketAsyncEventArg associated with the completed accept operation.</param>
private void OnAcceptCompleted(object sender, SocketAsyncEventArgs e)
{
ProcessAccept(e);
}

/// <summary>
/// 監聽Socket接受處理
/// </summary>
/// <param name="e">SocketAsyncEventArg associated with the completed accept operation.</param>
private void ProcessAccept(SocketAsyncEventArgs e)
{
if (e.SocketError == SocketError.Success)
{
Socket s = e.AcceptSocket;//和客戶端關聯的socket
if (s.Connected)
{
try
{

Interlocked.Increment(ref _clientCount);//原子操做加1
SocketAsyncEventArgs asyniar = _objectPool.Pop();
asyniar.UserToken = s;

Log4Debug(String.Format("客戶 {0} 連入, 共有 {1} 個鏈接。", s.RemoteEndPoint.ToString(), _clientCount));

if (!s.ReceiveAsync(asyniar))//投遞接收請求
{
ProcessReceive(asyniar);
}
}
catch (SocketException ex)
{
Log4Debug(String.Format("接收客戶 {0} 數據出錯, 異常信息： {1} 。", s.RemoteEndPoint, ex.ToString()));
//TODO 異常處理
}
//投遞下一個接受請求
StartAccept(e);
}
}
}

#endregion

#region 發送數據

/// <summary>
/// 異步的發送數據
/// </summary>
/// <param name="e"></param>
/// <param name="data"></param>
public void Send(SocketAsyncEventArgs e, byte[] data)
{
if (e.SocketError == SocketError.Success)
{
Socket s = e.AcceptSocket;//和客戶端關聯的socket
if (s.Connected)
{
Array.Copy(data, 0, e.Buffer, 0, data.Length);//設置發送數據

//e.SetBuffer(data, 0, data.Length); //設置發送數據
if (!s.SendAsync(e))//投遞發送請求，這個函數有可能同步發送出去，這時返回false，而且不會引起SocketAsyncEventArgs.Completed事件
{
// 同步發送時處理髮送完成事件
ProcessSend(e);
}
else
{
CloseClientSocket(e);
}
}
}
}

/// <summary>
/// 同步的使用socket發送數據
/// </summary>
/// <param name="socket"></param>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="size"></param>
/// <param name="timeout"></param>
public void Send(Socket socket, byte[] buffer, int offset, int size, int timeout)
{
socket.SendTimeout = 0;
int startTickCount = Environment.TickCount;
int sent = 0; // how many bytes is already sent
do
{
if (Environment.TickCount > startTickCount + timeout)
{
//throw new Exception("Timeout.");
}
try
{
sent += socket.Send(buffer, offset + sent, size - sent, SocketFlags.None);
}
catch (SocketException ex)
{
if (ex.SocketErrorCode == SocketError.WouldBlock ||
ex.SocketErrorCode == SocketError.IOPending ||
ex.SocketErrorCode == SocketError.NoBufferSpaceAvailable)
{
// socket buffer is probably full, wait and try again
Thread.Sleep(30);
}
else
{
throw ex; // any serious error occurr
}
}
} while (sent < size);
}


/// <summary>
/// 發送完成時處理函數
/// </summary>
/// <param name="e">與發送完成操做相關聯的SocketAsyncEventArg對象</param>
private void ProcessSend(SocketAsyncEventArgs e)
{
if (e.SocketError == SocketError.Success)
{
Socket s = (Socket)e.UserToken;

//TODO
}
else
{
CloseClientSocket(e);
}
}

#endregion

#region 接收數據


/// <summary>
///接收完成時處理函數
/// </summary>
/// <param name="e">與接收完成操做相關聯的SocketAsyncEventArg對象</param>
private void ProcessReceive(SocketAsyncEventArgs e)
{
if (e.SocketError == SocketError.Success)//if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success)
{
// 檢查遠程主機是否關閉鏈接
if (e.BytesTransferred > 0)
{
Socket s = (Socket)e.UserToken;
//判斷全部需接收的數據是否已經完成
if (s.Available == 0)
{
//從偵聽者獲取接收到的消息。
//String received = Encoding.ASCII.GetString(e.Buffer, e.Offset, e.BytesTransferred);
//echo the data received back to the client
//e.SetBuffer(e.Offset, e.BytesTransferred);

byte[] data = new byte[e.BytesTransferred];
Array.Copy(e.Buffer, e.Offset, data, 0, data.Length);//從e.Buffer塊中複製數據出來，保證它可重用

string info=Encoding.Default.GetString(data);
Log4Debug(String.Format("收到 {0} 數據爲 {1}",s.RemoteEndPoint.ToString(),info));
//TODO 處理數據

//增長服務器接收的總字節數。
}

if (!s.ReceiveAsync(e))//爲接收下一段數據，投遞接收請求，這個函數有可能同步完成，這時返回false，而且不會引起SocketAsyncEventArgs.Completed事件
{
//同步接收時處理接收完成事件
ProcessReceive(e);
}
}
}
else
{
CloseClientSocket(e);
}
}

#endregion

#region 回調函數

/// <summary>
/// 當Socket上的發送或接收請求被完成時，調用此函數
/// </summary>
/// <param name="sender">激發事件的對象</param>
/// <param name="e">與發送或接收完成操做相關聯的SocketAsyncEventArg對象</param>
private void OnIOCompleted(object sender, SocketAsyncEventArgs e)
{
// Determine which type of operation just completed and call the associated handler.
switch (e.LastOperation)
{
case SocketAsyncOperation.Accept:
ProcessAccept(e);
break;
case SocketAsyncOperation.Receive:
ProcessReceive(e);
break;
default:
throw new ArgumentException("The last operation completed on the socket was not a receive or send");
}
}

#endregion

#region Close
/// <summary>
/// 關閉socket鏈接
/// </summary>
/// <param name="e">SocketAsyncEventArg associated with the completed send/receive operation.</param>
private void CloseClientSocket(SocketAsyncEventArgs e)
{
Log4Debug(String.Format("客戶 {0} 斷開鏈接!",((Socket)e.UserToken).RemoteEndPoint.ToString()));
Socket s = e.UserToken as Socket;
CloseClientSocket(s, e);
}

/// <summary>
/// 關閉socket鏈接
/// </summary>
/// <param name="s"></param>
/// <param name="e"></param>
private void CloseClientSocket(Socket s, SocketAsyncEventArgs e)
{
try
{
s.Shutdown(SocketShutdown.Send);
}
catch (Exception)
{
// Throw if client has closed, so it is not necessary to catch.
}
finally
{
s.Close();
}
Interlocked.Decrement(ref _clientCount);
_maxAcceptedClients.Release();
_objectPool.Push(e);//SocketAsyncEventArg 對象被釋放，壓入可重用隊列。
}
#endregion

#region Dispose
/// <summary>
/// Performs application-defined tasks associated with freeing,
/// releasing, or resetting unmanaged resources.
/// </summary>
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}

/// <summary>
/// Releases unmanaged and - optionally - managed resources
/// </summary>
/// <param name="disposing"><c>true</c> to release
/// both managed and unmanaged resources; <c>false</c>
/// to release only unmanaged resources.</param>
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
try
{
Stop();
if (_serverSock != null)
{
_serverSock = null;
}
}
catch (SocketException ex)
{
//TODO 事件
}
}
disposed = true;
}
}
#endregion

public void Log4Debug(string msg)
{
Console.WriteLine("notice:"+msg);
}

}
}

BufferManager.cs 這個類是緩存管理類，是採用MSDN上面的例子同樣的 地址: https://msdn.microsoft.com/zh-cn/library/bb517542.aspx

SocketAsyncEventArgsPool.cs 這個類也是來自MSDN的 地址:https://msdn.microsoft.com/zh-cn/library/system.net.sockets.socketasynceventargs.aspx

須要的話本身到MSDN網站上去取，我就不貼出來了

服務器端

static void Main(string[] args)
{

IOCPServer server = new IOCPServer(8088, 1024);
server.Start();
Console.WriteLine("服務器已啓動....");
System.Console.ReadLine();
}

客戶端

客戶端代碼也是很簡單
static void Main(string[] args)
{
IPAddress remote=IPAddress.Parse("192.168.3.4");
client c = new client(8088,remote);

c.connect();
Console.WriteLine("服務器鏈接成功!");
while (true)
{
Console.Write("send>");
string msg=Console.ReadLine();
if (msg == "exit")
break;
c.send(msg);
}
c.disconnect();
Console.ReadLine();
}

client.cs
public class client
{

public TcpClient _client;

public int port;

public IPAddress remote;

public client(int port,IPAddress remote)
{

this.port = port;
this.remote = remote;
}

public void connect()
{
this._client=new TcpClient();
_client.Connect(remote, port);
}
public void disconnect()
{
_client.Close();
}
public void send(string msg)
{
byte[] data=Encoding.Default.GetBytes(msg);
_client.GetStream().Write(data, 0, data.Length);
}
}

IOCPClient類，使用SocketAsyncEventArgs類創建一個Socket客戶端。雖然MSDN說這個類特別設計給網絡服務器應用，但也沒有限制在客戶端代碼中使用APM。下面給出了IOCPClient類的樣例代碼： public class IOCPClient { /// <summary> /// 鏈接服務器的socket /// </summary> private Socket _clientSock; /// <summary> /// 用於服務器執行的互斥同步對象 /// </summary> private static Mutex mutex = new Mutex(); /// <summary> /// Socket鏈接標誌 /// </summary> private Boolean _connected = false; private const int ReceiveOperation = 1, SendOperation = 0; private static AutoResetEvent[] autoSendReceiveEvents = new AutoResetEvent[] { new AutoResetEvent(false), new AutoResetEvent(false) }; /// <summary> /// 服務器監聽端點 /// </summary> private IPEndPoint _remoteEndPoint; public IOCPClient(IPEndPoint local,IPEndPoint remote) { _clientSock = new Socket(local.AddressFamily,SocketType.Stream, ProtocolType.Tcp); _remoteEndPoint = remote; } #region 鏈接服務器 /// <summary> /// 鏈接遠程服務器 /// </summary> public void Connect() { SocketAsyncEventArgs connectArgs = new SocketAsyncEventArgs(); connectArgs.UserToken = _clientSock; connectArgs.RemoteEndPoint = _remoteEndPoint; connectArgs.Completed += new EventHandler<SocketAsyncEventArgs>(OnConnected); mutex.WaitOne(); if (!_clientSock.ConnectAsync(connectArgs))//異步鏈接 { ProcessConnected(connectArgs); } } /// <summary> /// 鏈接上的事件 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> void OnConnected(object sender, SocketAsyncEventArgs e) { mutex.ReleaseMutex(); //設置Socket已鏈接標誌。 _connected = (e.SocketError == SocketError.Success); } /// <summary> /// 處理鏈接服務器 /// </summary> /// <param name="e"></param> private void ProcessConnected(SocketAsyncEventArgs e) { //TODO } #endregion #region 發送消息 /// <summary> /// 向服務器發送消息 /// </summary> /// <param name="data"></param> public void Send(byte[] data) { SocketAsyncEventArgs asyniar = new SocketAsyncEventArgs(); asyniar.Completed += new EventHandler<SocketAsyncEventArgs>(OnSendComplete); asyniar.SetBuffer(data, 0, data.Length); asyniar.UserToken = _clientSock; asyniar.RemoteEndPoint = _remoteEndPoint; autoSendReceiveEvents[SendOperation].WaitOne(); if (!_clientSock.SendAsync(asyniar))//投遞發送請求，這個函數有可能同步發送出去，這時返回false，而且不會引起SocketAsyncEventArgs.Completed事件 { // 同步發送時處理髮送完成事件 ProcessSend(asyniar); } } /// <summary> /// 發送操做的回調方法 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnSendComplete(object sender, SocketAsyncEventArgs e) { //發出發送完成信號。 autoSendReceiveEvents[SendOperation].Set(); ProcessSend(e); } /// <summary> /// 發送完成時處理函數 /// </summary> /// <param name="e">與發送完成操做相關聯的SocketAsyncEventArg對象</param> private void ProcessSend(SocketAsyncEventArgs e) { //TODO } #endregion #region 接收消息 /// <summary> /// 開始監聽服務端數據 /// </summary> /// <param name="e"></param> public void StartRecive(SocketAsyncEventArgs e) { //準備接收。 Socket s = e.UserToken as Socket; byte[] receiveBuffer = new byte[255]; e.SetBuffer(receiveBuffer, 0, receiveBuffer.Length); e.Completed += new EventHandler<SocketAsyncEventArgs>(OnReceiveComplete); autoSendReceiveEvents[ReceiveOperation].WaitOne(); if (!s.ReceiveAsync(e)) { ProcessReceive(e); } } /// <summary> /// 接收操做的回調方法 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnReceiveComplete(object sender, SocketAsyncEventArgs e) { //發出接收完成信號。 autoSendReceiveEvents[ReceiveOperation].Set(); ProcessReceive(e); } /// <summary> ///接收完成時處理函數 /// </summary> /// <param name="e">與接收完成操做相關聯的SocketAsyncEventArg對象</param> private void ProcessReceive(SocketAsyncEventArgs e) { if (e.SocketError == SocketError.Success) { // 檢查遠程主機是否關閉鏈接 if (e.BytesTransferred > 0) { Socket s = (Socket)e.UserToken; //判斷全部需接收的數據是否已經完成 if (s.Available == 0) { byte[] data = new byte[e.BytesTransferred]; Array.Copy(e.Buffer, e.Offset, data, 0, data.Length);//從e.Buffer塊中複製數據出來，保證它可重用 //TODO 處理數據 } if (!s.ReceiveAsync(e))//爲接收下一段數據，投遞接收請求，這個函數有可能同步完成，這時返回false，而且不會引起SocketAsyncEventArgs.Completed事件 { //同步接收時處理接收完成事件 ProcessReceive(e); } } } } #endregion public void Close() { _clientSock.Disconnect(false); } /// <summary> /// 失敗時關閉Socket，根據SocketError拋出異常。 /// </summary> /// <param name="e"></param> private void ProcessError(SocketAsyncEventArgs e) { Socket s = e.UserToken as Socket; if (s.Connected) { //關閉與客戶端關聯的Socket try { s.Shutdown(SocketShutdown.Both); } catch (Exception) { //若是客戶端處理已經關閉，拋出異常 } finally { if (s.Connected) { s.Close(); } } } //拋出SocketException throw new SocketException((Int32)e.SocketError); } /// <summary> /// 釋放SocketClient實例 /// </summary> public void Dispose() { mutex.Close(); autoSendReceiveEvents[SendOperation].Close(); autoSendReceiveEvents[ReceiveOperation].Close(); if (_clientSock.Connected) { _clientSock.Close(); } } }這個類我沒有測試，可是理論上是沒問題的。本文地址:http://blog.csdn.net/zhujunxxxxx/article/details/43573879--------------------- 做者：小竹zz 來源：CSDN 原文：https://blog.csdn.net/zhujunxxxxx/article/details/43573879 版權聲明：本文爲博主原創文章，轉載請附上博文連接！