Re: Java Threads on Windows, multi-core processor...

From:

Knute Johnson <nospam@rabbitbrush.frazmtn.com>

Newsgroups:

comp.lang.java.programmer

Date:

Tue, 26 Feb 2008 15:19:14 -0800

Message-ID:

<47c466f7$0$5828$b9f67a60@news.newsdemon.com>

Daniel Pitts wrote:

I have a program I'm working on (a ray tracer to be exact) that uses
multiple threads to do the hard work.
According to windows task manager, I'm only utilizing around 50%(?10%)of
my CPU power.

This makes me think that either I'm spending too much time synchronizing
(darn), or I'm only using one CPU.

Anyone have suggestions on which it is? I'm using a BlockingDeque to
pass my work load off to worker threads, and I thought that wouldn't
have a lot of synch cost to it.

On Windows with a Pentium D processor and only one thread running, the
processors run at a total of about 50%, one using 60% and the other 40%.
  If I run two threads, then both run at 100%. I don't know what this
means but it is interesting. I think there are a lot of scheduling
issues that are obscured.

public class test7 implements Runnable {
     public void run() {
         while (true) ;
     }
     public static void main(String[] args) {
         new Thread(new test7()).start();
         new Thread(new test7()).start();
     }
}

--

Knute Johnson
email s/nospam/knute/

--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
      ------->>>>>>http://www.NewsDemon.com<<<<<<------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access