topic Re: 100% CPU Bottleneck in Operating System - HP-UX

100% CPU Bottleneck

PSS SYS ADMIN — Mon, 23 Sep 2002 08:01:08 GMT

Hi everyone,
I have a K250 with 2 cpus with an application (Vision64) that take the system to the 100% of used resources.
Can you suggest me a better way to optimize the kernel parameters so I override the bottleneck problem?

* Tunable parameters

STRMSGSZ 65535
dbc_max_pct 20
maxfiles 2048
maxfiles_lim 2048
maxswapchunks 1024
maxuprc 1000
nfile 4096
nflocks 1024
ninode 4096
nproc 1024
nstrpty 60

Regards...
PSS

Re: 100% CPU Bottleneck

Animesh Chakraborty — Mon, 23 Sep 2002 08:12:42 GMT

Hi,
Please see the attached documents

Re: 100% CPU Bottleneck

PSS SYS ADMIN — Mon, 23 Sep 2002 11:00:44 GMT

In attachment,the kernel parameters.

Re: 100% CPU Bottleneck

harry d brown jr — Mon, 23 Sep 2002 11:48:21 GMT

answer is => Get a faster machine, more memory, and upgrade the OS

The oxymoron here is that vision64 is supposed to assist administrators not slap them down.

live free or die
harry

Re: 100% CPU Bottleneck

PSS SYS ADMIN — Mon, 23 Sep 2002 15:07:51 GMT

Can anyone of you take a watch to the kernel parameters in attachment and suggest me an improvement.

- The OS is hpux 11.00
- model K250
- Memory 1Gb
- Swap = 2Gb
- 2 cpu
The application is Vision64 for the software distribution. It opens a lot of connections to several clients at a time.

Please suggest me something.

Regards...
PSS

Re: 100% CPU Bottleneck

Anil C. Sedha — Mon, 23 Sep 2002 15:31:47 GMT

Hi,

I would suggest the following looking at your attached document

bufpages - 235000

dbc_max_pct - 30

nproc - 8000

semmap - 1000

semmni - 500

I hope this helps you.

Regards,
Anil

Re: 100% CPU Bottleneck

PSS SYS ADMIN — Tue, 24 Sep 2002 10:23:31 GMT

I've applied the suggested kernel parameters and the result was:
SYSTEM PANIC!!!
The system returned an error like this: failed to allocate memory (cache error).
Something wrong in that parameters!

Regards...
PSS

Re: 100% CPU Bottleneck

Dave Wherry — Tue, 24 Sep 2002 12:50:54 GMT

If you are out of CPU resources (running 100%) tuning the kernel is not going to solve your problem. Of course, that assumes you have a problem.
Is the fact that CPU is %100 creating a problem? Are processes aborting or running very slow? If you do not have anything else running on this system let the application take 100%. If the applications are running OK you really do not have a problem.
If there are problems with jobs failing or running much too long, you do need an upgrade.

Re: 100% CPU Bottleneck

Shannon Petry — Tue, 24 Sep 2002 13:44:01 GMT

If a system reports CPU utilization of 100%, there is not much chance that tuning a parameter will reduce this.

Kind of like saying my disk is full, how can I tune the disk to reduce the used space?

Secondly, I'd give you no recommendations without knowing the rest of the story!
Memory and memory utilization,
summary from iostat/vmstat
swapinfo, etc...

Regards,
Shannon