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High CPU usage by Oracle processes

fly_fisher
Advisor

High CPU usage by Oracle processes

Hi you all,

I'm having a performance problem with a machine. The CPU is near 100%. After seeing what processes are the guilty ones I've seen they are some Oracle ones. I'm a newbie with Oracle. Here I send you the init.ora file. I'm afraid the DB is not well dimensioned. There are a lot of processes like:

oracle 28834 1 19 11:07:16 ? 0:00 oracleNMPROD (DESCRIPTION=(LOCAL=no)(ADDRESS=(PROTOCOL=BEQ))

they end very fast, but there are many of them each second.

So my question is, how could be reduced the CPU usage (if possible)?

Memory 512 MB
2 CPU's 450 MHZ
SO HPUX 11.0

Thank you very much for your help,
Regards.
Catch and release !!!!!!
6 REPLIES
fly_fisher
Advisor

Re: High CPU usage by Oracle processes

I forgot to say it's Oracle 8.1.6

Thanks.
Catch and release !!!!!!
Sanjay_6
Honored Contributor

Re: High CPU usage by Oracle processes

Hi Rafael,

Take a Look at this thread,

http://technet.oracle.com/doc/hp/server.804/A59371_01/ch3_opt.htm#8830

Hope this helps.

Regds
A. Clay Stephenson
Acclaimed Contributor

Re: High CPU usage by Oracle processes

The very first thing to check is the value of the kernel tunable 'timeslice'. There has been a Tuned Parameter set for databases that wrongly set timeslice to 1 rather than 10.
If it ain't broke, I can fix that.
fly_fisher
Advisor

Re: High CPU usage by Oracle processes

Hi A.Clay,

timeslice is 10;

Thank you very much. I've seen in Glance that the CPU is being used mainly by these system calls:

System Call Name ID Count Rate CPU Time Cum CPU
--------------------------------------------------------------------------------
exit
1 446 91.0 0.62159 148.23025
fork 2 984 189.2 0.43792 107.06064
Catch and release !!!!!!
MANOJ SRIVASTAVA
Honored Contributor

Re: High CPU usage by Oracle processes

Hi Rafael

With the information you ahve provided , the first thing look like is that you ahve a lesser memory , can you porst a o/p of like sar 2 5 which shouls the CPU usage , also waht are the kernel parameters of HP UX . The best way to figure out would be know is really CPU used for more memory i/o , what is the swap size , mem utilization etc , physical , logical reads , etc .

A good palce to star would be to post the sar o/p , and also vmstat o/p .

If you are sure taht it is not the OS and the same is proeperly tuned then you amy look at the following :

http://web.singnet.com.sg/~petermag/tune.html


Manoj Srivastava
Jim Butler
Valued Contributor

Re: High CPU usage by Oracle processes

try metalink.oracle.com, and enter your oracle sid to set yourself up for some really good tech docs. With oracle, it could be just about anything. I posted my oracle kernel that I use here to support 3 SIDS on one of our oracle boxes here.

Are you running a listener process, and if so, are you communication with a webserver?
or
Are you running a stand alone OLTP system where you are serving terms to your users, etc.?

Man The Bilge Pumps!