topic Re: Decrease memory usage in Operating System - HP-UX

Decrease memory usage

Muttikkal_1 — Thu, 18 Oct 2007 07:19:59 GMT

My system having oracle database
While it coming up ( check points ),getting crashed due to less memory space availability
How can i manage my memory usage for bring down the load on memory.
regards
praveen muttikkal

Re: Decrease memory usage

Bill Hassell — Thu, 18 Oct 2007 08:11:22 GMT

There are many, many comments here in the forums about properly configuring HP-UX and the environment for Oracle. If all you want to do is reduce memory usage, tell your database administrator to reconfigure Oracle to use less memory. That will have a negative effect on performance but shared memory usage will go down. Also make sure your kernel parameters for the dynamic buffer cache (dbc_min_pct and dcb_max_pct) are set to use between 400 and 1000 MB of RAM.

What version of HP-UX are you running? What is the model of the computer you are using. How much RAM do you have? What version of Oracle are you running? Without this information, it is not possible to give a useful recommendation.

Re: Decrease memory usage

Frank de Vries — Thu, 18 Oct 2007 10:43:11 GMT

Rule of thumb:

For one oracle instance use
maximum 1/3rd of total unix memory
for sga.
For multiple oracle instances use
50% of total unix memory (approportionated
between x instances)

For a basic Oracle instance you can try:
db_block_size = 4096
open_cursors = 200
max_enabled_roles = 30
db_block_buffers = 7500

shared_pool_size = 64000000
large_pool_size = 12000000
java_pool_size = 25971520

log_checkpoint_interval = 122880
log_checkpoint_timeout = 7200

With this most basic configuration in your
parameter file it should not crash.
Although, there is one but, you need
to check the size of your redo logs
can handle transaction volume.
Otherwise performance will be bad.

Please check your alert log for messages
and check the redo cycle is at least 5 minutes apart.

IF you need more explaination let us know:)

Re: Decrease memory usage

Hein van den Heuvel — Thu, 18 Oct 2007 11:07:33 GMT

Please report the EXACT error message you observed and explain WHERE you found to, and WHAT command is being executed.

The posting you made so far lost too much in interpretation / translation

Also check the ALERT LOG frot the DB for further details and context for the error.

You may want to include arelevan chunk (a few lines before and after the error) from the alert log in a future reply, or attach that as a text file to a reply.

You may also want to provide a little more details on the scenario and pertinent details.
- Did it ever work?
- What changed? What did not change? :-)
- How much memory? New / more consumers

Good luck,
Hein.

Re: Decrease memory usage

Muttikkal_1 — Thu, 18 Oct 2007 22:43:25 GMT

Thanks ALL

Re: Decrease memory usage

whiteknight — Fri, 19 Oct 2007 02:12:13 GMT

Hi muttikkal,

Are you using 11.23 ? if you are using 11.23 there was ways to reduce your memory load.

Common misconfigured hpux resources
http://docs.hp.com/en/5992-0732/5992-0732.pdf

WK

Re: Decrease memory usage

Hein van den Heuvel — Fri, 19 Oct 2007 09:04:49 GMT

>>> Thanks ALL

Thanks for what?
We are curious... such that we can help others, and perhaps our own customer better should this happen again.

What was the problem / solution?
What was the actual error?

Is it the suggestions here to look in detail at the error message(s) which helped you to solve the problem yourself?
The '2' and '3' points awards ('thanks for playing but no thanks') suggests to me something completely different was happening.

What is/was the meaning of the riddle: "getting crashed due to less memory space availability"

Regards,
Hein.