topic Increase Value of kernel parameter range in Operating System - HP-UX

Increase Value of kernel parameter range

Manuel_8 — Thu, 31 Oct 2002 14:37:11 GMT

Hello guy,
I must increase the value kernel's parameter shmmni from 200 to 3248, but the maximum range for this parameter is 1024;
Can you indicate, if possible, increase the value of range?

Please help me

Manuel

Re: Increase Value of kernel parameter range

Christopher McCray_1 — Thu, 31 Oct 2002 14:40:32 GMT

Hello,

How much memory do you have in the system?

Look at this link:

http://docs.hp.com/hpux/onlinedocs/939/KCParms/KCparam.ShMmni.html

The upper limit is memory constrained, and look at the note concerning the 1024 value.

I have large N-class db servers and I have values ranging from 512-1024.

Hope this helps

Chris

Re: Increase Value of kernel parameter range

Manuel_8 — Thu, 31 Oct 2002 14:57:31 GMT

Thenks
I have a L3000 whit 2GB of memory, my maximum limit is 1024.
Can I increase this limit?

Thenks

MAnuel

Re: Increase Value of kernel parameter range

Christopher McCray_1 — Thu, 31 Oct 2002 15:03:03 GMT

Hello again,

I also should have asked what version of OS you are running. The link I gave you is for 11.00. If you run the sysdef command and look at the column MIN-MAX, this is the value range you can enter, which for 11.00 is 1024.

For 11i, it appears to be larger, quote:

Maximum: 1024 for a 32 bit kernel, and 8192 for a 64 bit kernel

Reference: the Tunable parameters guide for 11i, shmmni page:

http://docs.hp.com/hpux/onlinedocs/TKP-90202/TKP-90202.html

Hope this helps

Re: Increase Value of kernel parameter range

Ravi_8 — Thu, 31 Oct 2002 15:06:59 GMT

Hi, Manuel

sure you can increase.

first have a backup of existing kernel.

#kmtune -s shmmni=3248
# cd /stand/build
#mk_kernel
once the kernel builds successfully
#mv vmunix_test /stand/vmunix
#reboot

now the shmmni values will be set to 3248

Re: Increase Value of kernel parameter range

Manuel_8 — Thu, 31 Oct 2002 15:25:28 GMT

Thenks for helps,
I have 11i.
Is it possible increase maximum value of the kernel parameter range? What I do to increase.
Please help me

Manuel

Re: Increase Value of kernel parameter range

Bill Hassell — Thu, 31 Oct 2002 21:26:21 GMT

Are you sure you need more than 3,000 shared memory segments? Is this for a single program? If so, the designer needs to go back to work. If this is because there are 3,000 programs that all need a separate shared memory segment, then I'm confused as to why shared memory is being used at all.

Perhaps the number you need is the maximum size of a single shared memory segment, in which case, your application needs to be rewritten for 64bit mode.

The uppoer limit is a kernel limitation and cannot be changed.