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nn3003
28-May-2012, 13:02
Hello !

I have SLES 11 SP1 and I am running Oracle Database on it. It uses shared memory. By default after installation I have some amount of shared memory /dev/shm
tmpfs 7.8G 3.8G 4.1G 49% /dev/shm
How can I change this value ? I think by default is is 50 percent of system memory, I need to change it to different value. What configuration parameter do I need to change ? Is it in yast ? /etc/sysconfig ?

Thank you for answer !

Magic31
30-May-2012, 08:31
Hello !

I have SLES 11 SP1 and I am running Oracle Database on it. It uses shared memory. By default after installation I have some amount of shared memory /dev/shm
tmpfs 7.8G 3.8G 4.1G 49% /dev/shm
How can I change this value ? I think by default is is 50 percent of system memory, I need to change it to different value. What configuration parameter do I need to change ? Is it in yast ? /etc/sysconfig ?

Thank you for answer !

Hi,

These are kernel parameters you are looking to set (like kernel.shmmax / shmall / shmmni) which can be set in /etc/sysctl.conf to have the desired values set across reboots.

This is an older guide based on SLES 9and Oracle 10g but still applies where to find what, do check the Oracle documentation of the version you are using to find the recommended values suited : http://www.puschitz.com/InstallingOracle10gOnSUSE.shtml


Hope that helps,
Willem

enovaklbank
04-Jun-2012, 15:22
Yes, by default it has the size of system-ram/2.
You can enlarge it by remounting it with a different size, e.g.:
mount -o remount,size=9G /dev/shm

or make it permanent by adding a line to /etc/fstab, e.g.:

none /dev/shm tmpfs remount,size=9G 0 0

Magic31
04-Jun-2012, 20:11
Yes, by default it has the size of system-ram/2.
You can enlarge it by remounting it with a different size, e.g.:
mount -o remount,size=9G /dev/shm

or make it permanent by adding a line to /etc/fstab, e.g.:

none /dev/shm tmpfs remount,size=9G 0 0

Interesting... never looked at this in depth, but this is different to what can be set in sysctl?

-Willem