How to Push Java Performance to Its Limit

Hi there,

I use java version 1.4.2.09 in HP-UX with 8 CPUs and 4GB Memories.

I add -Xmx3072m & -Xms3072m parameters in a startup of certain java application.

the java and the application run well. But, it use only 120%CPU. It means that it only use 2 CPUs.

The question is: How can I make the java application run using all available resources (8 CPUs)?

I have tuned the memory to reach almost 4GB (3072M), now all its left is how to maximize CPU usage to almost 800% (all CPUs are used).

is there any clue for this?

thanks

[578 byte] By [complex2004a] at [2007-11-26 13:30:44]

# 1

You may not have written your application in a way that it can use all 8 cpu's concurrently.

Run the code below. It should use all 8 of your CPU's.

public class Spin implements Runnable {

public static void main(String[] args) {

int threads = Runtime.getRuntime().availableProcessors();

if (args.length > 0) {

threads = Integer.parseInt(args[0]);

}

for (int i=0; i<threads; i++) {

new Thread(new Spin(),"Spin " + i).start();

}

public void run() {

for(long i=0; i><10000000000; i++) {

if (i % 10000000 == 0) {

System.out.println("Thread \"" + Thread.currentThread().getName() + "\" is on iteration " + i);

}

Caffeine0001a at 2007-7-7 20:36:56 >

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