topic Re: 100% CPU Usage when running a Java Application in Operating System - HP-UX

100% CPU Usage when running a Java Application

Achint Kalra — Mon, 28 Jun 2004 04:20:28 GMT

Hi,

I have heavily multithreaded Java 2 application running on HP UX 11.0. When I run this application with the root user, the application runs fine. But when I run the same application using some other user login, the application hangs and the CPU utilization reaches 98%. I have tested the application on WinXP also but it runs fine.

Thanks and Regards
Achint

Re: 100% CPU Usage when running a Java Application

Muthukumar_5 — Mon, 28 Jun 2004 05:17:09 GMT

hai,

Threaded application's on 11.00 environment is having some limitations. We have to tune two kernel parameters to achieve a good response from the application.

Refer this link.
http://www.hp.com/products1/unix/java/infolibrary/prog_guide/java1/configuration.html

We have to tune nkthread and max_thread_proc parameters and user limits.

Regards,
Muthukumar.

Re: 100% CPU Usage when running a Java Application

Achint Kalra — Mon, 28 Jun 2004 05:55:57 GMT

Thanks muthu,

But I have already updated these configurations as nkthread = 6000 and max_thread_proc = 3000 and my application is still hanging. Number of active threads in the application is not more than 500.
Can you please suggest me some more reasons for application hang?
FYI Java version is 1.4.2.03

Regards
Achint

Re: 100% CPU Usage when running a Java Application

Muthukumar_5 — Mon, 28 Jun 2004 06:07:14 GMT

hai,

Thread applications can be hung,when the allocated resource is not adaquate to it. It may get some SIGNAL's because of memory accessing problem.

Test that application with more limits on threads. May be some other application use that threads. Memory access voilation problem may be happened.

Are you getting any more messages during the hang-up. use the jdb to debug the application.

Check this link:
http://www.hp.com/products1/unix/java/infolibrary/prog_guide/java1/debugging.html

Regards,
Muthukumar.