RHEL Kernel Parameters

[Former Member]

Hello,

We have RHEL v6.x in our landscape. As per the SAP Note-1496410  "kernel.msgmni " should be set to "1024".

But when we checked on vm kernel.msgmni param through sysclt -a default value set to 32768.

Do we need to change the parameter value to 1024? or ok to keep default value 32768?

Thanks and Regards,

Prasad

[former_member182657 · Accepted solution]

Hi Prasad,

Do we need to change the parameter value to 1024? or ok to keep default value 32768?

As per SAP Note 1496410  which you shared kernel.msgmni should be present with value of 1024 as prerequisites.

In response to your query my answer would be yes of-course you need to change the value of this parameter from 32768 to 1024 as per SAP Note recommendations.The play behind this value just is, if the value of parameter is set with the highest value,the message queue may exhaust the complete OS kernel & can cause KERNEL PANIC ,after that you knows what could you loose.To overcome or to prevent such type of issues SAP provided specific values for such OS parameters.

So i suggest you to set this value with 1024 instead of 32768 & proceed with the procedures.

Hope i explained well & will be helpful .

Good luck !!

[Former Member]

From SAP note 1496410:

Some Linux kernel parameters have to be adjusted to meet the requirements of SAP software. To do this append the following lines to /etc/sysctl.conf, or change the already existing parameters accordingly (these are the required minimum values, higher values are okay as well😞


# SAP settings
kernel.msgmni=1024
kernel.sem=1250 256000 100 1024
vm.max_map_count=2000000 (see SAP Note 900929 for more information)