Name: dbT83986 Date: 07/01/99


my project used pipe communication of process.
SOLARIS PIPE-IO is very slow. but, windows is no problem.
this problem confirmed JDK 1.1.3 and 1.2.0.
may be, this problem exist all version of 1.1.x and 1.2.x

****************************************************************
Test Program Source
****************************************************************
//
// pipe communication test program.
// run: java pipe.Test
//
package pipe;

import java.io.*;

public class Test {

  void Client() {
    System.out.println("pipe test program");
    try {
      String command = "java -classpath " + System.getProperty("java.class.path") + " " + getClass().getName() + " -S";
      Runtime rt = Runtime.getRuntime();
      Process ps = rt.exec(command);
      InputStream in = ps.getInputStream();
      OutputStream out = ps.getOutputStream();
      System.out.println("wait for pipe server to ready ...");
      synchronized (this) {
        while (in.available() == 0)
          wait(1000);
      }
      long ct = System.currentTimeMillis();
      while (true) {
        int c = in.read();
        out.write(c);
        out.flush();
        if (c == 0)
          break;
        System.out.println("read data = " + c + " (" + (System.currentTimeMillis() - ct) + ")");
      }
      ct = System.currentTimeMillis() - ct;
      System.out.println("pipe communication time = " + ct + " msec");
    }
    catch (Exception e) {
      e.printStackTrace();
    }
    try { System.in.read(); } catch (Exception e) {}
  }

  void Server() {
    try {
      for (int c = 1; c <= 10; c++) {
        System.out.write(c);
        System.out.flush();
        if (System.in.read() != c)
          break;
      }
    }
    catch (Exception e) {
      e.printStackTrace();
    }
    System.out.write(0);
    System.out.flush();
    try { System.in.read(); } catch (Exception e) {}
  }

  public static void main(String[] args) {
    Test test = new Test();
    if ((args.length > 0) && args[0].equals("-S"))
      test.Server();
    else
      test.Client();
  }
}

****************************************************************
[Result of Windows] (same 1.1.6 and 1.2.1)
****************************************************************
pipe test program
wait for pipe server to ready ...
read data = 1 (0)
read data = 2 (0)
read data = 3 (0)
read data = 4 (0)
read data = 5 (0)
read data = 6 (0)
read data = 7 (0)
read data = 8 (0)
read data = 9 (60)
read data = 10 (60)
pipe communication time = 60 msec

****************************************************************
[Result of Soralis] (same 1.1.3 and 1.2.0)
****************************************************************
pipe test program
wait for pipe server to ready ...
read data = 1 (2)
read data = 2 (1010) problem. ??? 1 second delayed. ???
read data = 3 (2020) problem. ??? 1 second delayed. ???
read data = 4 (3030) problem. ??? ... ???
read data = 5 (4040)
read data = 6 (5050)
read data = 7 (6060)
read data = 8 (7070)
read data = 9 (8080)
read data = 10 (9090)
pipe communication time = 10100 msec

****************************************************************
[Result of Solaris: JDK Core Class to Update] (1.2.0)
****************************************************************
pipe test program
wait for pipe server to ready ...
read data = 1 (2)
read data = 2 (7)
read data = 3 (8)
read data = 4 (9)
read data = 5 (10)
read data = 6 (11)
read data = 7 (12)
read data = 8 (14)
read data = 9 (15)
read data = 10 (16)
pipe communication time = 17 msec

****************************************************************
[Update Point of Solaris JDK Core Class] (1.2.0)
****************************************************************
Source: src/solaris/classes/java/lang/UNIXProcess.java

class ProcessInputStream extends PipedInputStream implements Runnable {
  public void run() {
    ...
    while (true) {
      try {
        if ((nread = ins.read(buf)) < 0)
          break;
        outs.write(buf, 0, nread);
        ////////////////////////////////////////////////////////
        // point of update.
        // this flush operation are nothing in orignal source.
        outs.flush();
        ////////////////////////////////////////////////////////
      } catch (IOException e) {
        break;
      }
    }
    ...
  }
}
(Review ID: 85064)
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