cancel
Showing results for 
Search instead for 
Did you mean: 

shmmax limitation

ajitp
Occasional Contributor

shmmax limitation

I have the OS version 11.31.
I only need to Know, the recommended value for the shmmax parameter is 0x40000000000.
Also some time, on application level trace I get the error message like
shmget() of 17179869184 bytes failed. errno = 12(Not enough space)
Can I set it with the 8 GB RAM and 20 GB SWAP?

2 REPLIES
Dennis Handly
Acclaimed Contributor

Re: shmmax limitation

This hex value is way too big, two extra zeros?

Your colleague's thread?
http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1448163

While you can get 17 Gb, only if you have enough swap configured. What is "swapinfo -tam" when it fails?
SUDHAKAR_18
Trusted Contributor

Re: shmmax limitation

For database servers, ideal shmmax value is equal to physical memory.

find out the physical memory.
#dmesg |grep -i phy
or glance

calculate shmmax in bytes.
phy mem * 1024 *1024

tune the parameter.
#kctune shmmax=value