topic Re: Oracle memory issue. in Operating System - HP-UX

Oracle memory issue.

SDVICK — Wed, 24 Sep 2008 13:26:08 GMT

Hello all,

I'm fairly new to tuning Oracle on HP-UX (all my previous experience was with other DB types) so I'm hoping someone can help me with an issue that I'm having.

At least twice a week we run into an issue where Oracle (and it's associated applications) spins out of control and "eats" all of the memory and swap on the server. CPU and disk I/O is next to zero.

I checked swapinfo and less than 10% of the physical swap is being used.

Here are the system vitals:
Model: rp8420
CPU: 10
Memory: 16 Gb
Swap: 16 Gb (across 4 devices)
Oracle: 9.2.0.4 64bit

Does anyone have an idea of some things that I can check to try and relieve this pressure or is this something that I need to have my DBA's work w/ Oracle on?

Thanx in advanced.

Re: Oracle memory issue.

Steven E. Protter — Wed, 24 Sep 2008 13:34:01 GMT

Shalom,

You may have a memory leak. Memory leak detector:

http://www.hpux.ws/?p=8

General performance measurement.

http://www.hpux.ws/?p=6

SEP

Re: Oracle memory issue.

Oviwan — Wed, 24 Sep 2008 13:34:45 GMT

Hi

Oracle 9.2.0.4 is a really old version, if it's possible you should migrate to 9.2.0.8 or 10gR2 or even 11g.

What's the version of HPUX?
uname -a

What's the size of the SGA?
show parameter sga

Regards

Re: Oracle memory issue.

SDVICK — Wed, 24 Sep 2008 14:16:23 GMT

OS: HP-UX 11.11
SGA: 554 mb

Can't upgrade the DB at this time. Business won't let us.

Re: Oracle memory issue.

Oviwan — Wed, 24 Sep 2008 14:30:44 GMT

your sga is 554m and you have 16gb memory, does your application eats a lot of memory? if not extend your sga size.

and also check your buffer cache kernel parameter:
# kmtune | grep dbc
dbc_max_pct
dbc_min_pct

I think they are also to high. for more infos check this:
http://docs.hp.com/en/5991-0710/ch04s01.html

maybe some useful infos for swap:
http://docs.hp.com/en/1219/tuningwp.html#swap

HTH