shmmax value

[himacs]

Hi Admins,

I want to tune shmmax value equal to ram.

currently i have 6 gb ram and shmmax is 1073741824.

How can i calculate the new shmmax value

whether its like 1073741824*6

Please suggest on this

Regards
himacs

[johnsonpk · Accepted solution]

Hi Himacs
Currently you have 1 Gb (ie 1073741824 bytes)

>>whether its like 1073741824*6
Yes , You are right.

Johnson

[himacs]

Hi Johnson,

Thanks for the response

So what vakue i have to give with kctune or SAM..

kctune shmmax=?

Please suggest

Regards
himacs

[johnsonpk]

kctune shmmax=6442450944

[Johnson Punniyalingam]

Hope you have also "make_tape_recovery" for the OS backup.

Better if you could >SAM

SAM ->Kernel Configuration Configurable-> Parameters->Select shmmax->Actions -> Modify Configurable Parameter -> specify the value 1073741824*6 =

[madhuchakkaravarthy]

shmmax is dynamic so reboot is not necessary,,

but it is always welcome to take the os backup.

if not have the copy of vmunix and system in stand

regards

MC

[johnsonpk]

BY default kctune will prompt you for take a current kernel config backup

if you want to revert back the changes, you can use kconfig -l backup
if you want the system to be booted with the backed up kernel

use kconfig -n backup and reboot the server

[himacs]

Hi All,

I have changed the shmmax value to 6GB thro SAM.There was no renoot since the same is dynamic.

Thanks to johnsonpk for value calculating suggestion

regards
himacs

[Johnson Punniyalingam]

Congrats .!!

does the new value changes reflected ..? You can with below command

# kctune |grep shmmax

. if everything looks good. You may wish to close thread.avoid multiple posting :)

[himacs]

Hi Johnson,

Changes reflected in server.

Thanks for ur support

Regards
himacs