java - Java 中 RH Linux 和 Solaris 之间的 TCP 性能差异？

Question

在比较 RH Linux 和 Solaris 之间的 java TCP 套接字性能时，我的一项测试是通过使用 java 客户端发送字符串并从 java echo 服务器读取回复来完成的。我测量发送和接收数据所花费的时间(即环回往返)。

测试运行了 100,000 次(出现次数越多，结果相似)。根据我的测试，在具有默认系统和网络设置、相同 JVM 参数(如果有)等的同一台计算机上，Solaris 平均比 RH Linux 快 25/30%。

我不明白这么大的区别，我是否缺少某些系统/网络参数？

使用的代码(客户端和服务器)如​​下所示，如果有人有兴趣运行它(必须在命令行中给出出现次数):

import java.io.*;
import java.net.*;
import java.text.*;

public class SocketTest {

public final static String   EOF_STR = "EOF";
public final static String[] st      = {"toto"
    ,"1234567890"
    ,"12345678901234567890"
    ,"123456789012345678901234567890"
    ,"1234567890123456789012345678901234567890"
    ,"12345678901234567890123456789012345678901234567890"
    ,"123456789012345678901234567890123456789012345678901234567890"
};

public static void main(String[] args) throws UnknownHostException, IOException, InterruptedException {
    double mean = 0.0;
    int port = 30000;
    int times = Integer.parseInt(args[0]); 
    String resultFileName = "res.dat"; 
    new EchoServerSimple(port);        // instanciate and run
    Socket s = new Socket("127.0.0.1", port);        
    s.setTcpNoDelay(true);        
    PrintWriter pwOut = new PrintWriter(s.getOutputStream(), true);
    BufferedReader brIn = new BufferedReader(new InputStreamReader(s.getInputStream()));
    long[] res = new long[times];

    int j = 0;
    for(int i = 0; i < times; i++) {
        if(j >= st.length) j = 0;            
        long t0 = System.nanoTime();
        pwOut.println(st[j++]);
        brIn.readLine();
        res[i] = System.nanoTime() - t0;
        mean += ((double)res[i]) / times;
    }
    pwOut.println(EOF_STR);
    s.close();
    print(res, resultFileName);
    System.out.println("Mean = "+new DecimalFormat("#,##0.00").format(mean));
}

public static void print(long[] res, String output) {
    try {        
        PrintWriter pw;
        pw = new PrintWriter(new File(output));            
        for (long l : res) {
            pw.println(l);
        }
        pw.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
}

static class EchoServerSimple implements Runnable {

    private ServerSocket _serverSocket;

    public EchoServerSimple(int port) {
        try { _serverSocket = new ServerSocket(port); } 
        catch (IOException e) { e.printStackTrace(); }
        new Thread(this).start();
    }

    public void run() {
        try {
            Socket clientSocket = _serverSocket.accept();
            clientSocket.setTcpNoDelay(true);    
            PrintWriter pwOut = new PrintWriter(clientSocket.getOutputStream(), true);
            BufferedReader brIn = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));                
            try {
                while(true) {
                    String s = brIn.readLine();
                    pwOut.println(s);
                    if(s.equals(EOF_STR)) { clientSocket.close(); break;    }
                }
            } catch (Exception e) {
                e.printStackTrace(); 
                try { clientSocket.close(); } catch (IOException e1) { e1.printStackTrace(); }
            }
        } catch (IOException e) {e.printStackTrace(); }
    }
  }
}

我在单个 2.3GHz 双核 Nehalem 上为两个操作系统使用 JRE 1.6.0_18。2 个操作系统为 Solaris 10 和 RH Linux 5.4，带有 RT Kernel 2.6.24.7。

非常感谢。

Answer 1

可以在这里找到答案:https://serverfault.com/questions/157731/tcp-performance-differences-between-rh-linux-and-solaris-in-java