topic Re: shmmax !!! in Operating System - HP-UX

shmmax !!!

Venky_1 — Fri, 29 Mar 2002 10:21:12 GMT

Hello,

I need information/clarification on the shmmax parameter. I would like to know what should be the ideal value of shmmax if I have physical memory of 10GB and Oracle processes being used
are highly memory intensive.

Please suggest....

Thanks ..
Venky

Re: shmmax !!!

Tom Geudens — Fri, 29 Mar 2002 10:41:29 GMT

Hi,
I was going to post the links to some other threads about shmmax ... but there's so many good ones I suggest you simply do a search on itrc with keyword "shmmax".

This might be interesting as well
http://docs.hp.com/hpux/onlinedocs/os/KCparams.OverviewAll.html

Regards,
Tom Geudens

Re: shmmax !!!

Domenico_5 — Fri, 29 Mar 2002 10:43:54 GMT

The shmmax 'Single shared memory segment' is limited to 1 GB (0x40000000)
on a 32-bit HP-UX 11.0 system. When running under the 64-bit operating
system, shmmax is limited to 1 TB (0x10000000000).

The maximum shared memory accessible (all segments/quadrants) is limited
to 2.75 GB on 32-bit, and 4 TB on 64-bit HP-UX systems.

Re: shmmax !!!

Ceesjan van Hattum — Fri, 29 Mar 2002 10:52:08 GMT

shmmax should be 483183821 at minimum, but better to use 90% of the actual physical memory:
if you have 512 MB, use:
512*0,9*1024*1024.
if you have 10Gb, use:
1024*0,9*1024*1024 = 966367641

Greetings,
Ceesjan