Configure kernel

[Dewa Negara_4]

Hi All,

I tried to configure a static parameter with current value as "-" below.

Parameter Current Dyn Planned
==========================================
iomemsize - - 40000

I tried to use steps below:
1. cd /stand
2. /usr/lbin/sysadm/system_prep -v -s system
3. vi system and added on the last line "iomemsize 40000"
4. kmupdate
5. Reboot

But after rebooting, I tired to run kmtune again to check, but the value does not change.

[root@sihp8072:/stand]
# kmtune -q iomemsize
Parameter Current Dyn Planned Module Version
===============================================================================
iomemsize - - 40000

Anything wrong with the steps? How to configure this parameter?

Thanks for your help.

Best Regards,
Negara

[Wouter Jagers]

Between step 3 and 4 you forgot to issue mk_kernel.

It's best to generate your new system file in /stand/build instead of /stand, by the way.

# cd /stand/build
...
# mk_kernel -s /stand/build/system
# cp /stand/vmunix /stand/vmunix.prev
# cp /stand/system /stand/system.prev
# kmupdate

Cheers,
Wout

[Dewa Negara_4]

sorry...yes I did mk_kernel command. But forgot to add on the steps.

[Wouter Jagers]

Oh, ok :)

You write:
'3. vi system and added on the last line "iomemsize 40000"'

Your output after your boot:
'iomemsize - - 40000'

That seems correct, no ? 40000 in both cases ?


In case one of these numbers was mistyped, you could try it the 'supported' way:

Create the system file:
# cd /stand/build
# /usr/lbin/sysadm/system_prep -s system

Tune the parameter using kmtune:
# kmtune -S /stand/build/system -s iomemsize=40000

(or your required value)

Have kmtune check your change(s):
# kmtune -S /stand/build/system -d

(you should see your change in the output)

Then proceed with mk_kernel etc..

Cheers,
Wout

[Dewa Negara_4]

Thanks.

I think I did it. But still got no change on the parameter.

[root@sihp8072:/stand/build]
# kmtune -S /stand/build/system -s iomemsize=40000

[root@sihp8072:/stand/build]
# kmtune -S /stand/build/system -d
Parameter Current Dyn Planned Module Version
===============================================================================

[Wouter Jagers]

I just checked two of my HPUX boxes, and see the same thing:

Parameter Current Dyn Planned Module Version
===============================================================================
iomemsize - - 40000

..so I'm guessing it's ok.

However, I'm curious now. There is indeed no 'current' value shown (and we didn't make any changes to this).

I assume it's 'normal', maybe one of our olympians can clear this up ?

Cheers,
Wout

[Wouter Jagers]

I just double checked in a HPUX-book, and indeed. Even inthere the parameter shows up like this.

There's more parameters that show up like this (bootspinlocks, for example, and the swap-related params desfree, lotsfree and minfree, ..)

I can't provide you with a decent reason for this (yet), though :-/

..but at least we can assume all is ok ;-)

Cheers,
Wout

[Wouter Jagers]

..which should have made me realize the parameter probably can't be tuned. It'll be defined in the kernel.

Check out http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=66678&admit=-682735245+1173864466932+28353475

Cheers,
Wout

[Peter Godron · Accepted solution]

Hi,
the parameter does not appear on the list of configurable kernel parameters under SAM either, so suspect not tunable.

[Wouter Jagers]

Indeed. I meanwhile checked the list of tunables, and it's not inthere.

[Dewa Negara_4]

Hi All,

Thanks alot. So I no need to worry about this parameter. I just keep as it is.

Thanks again for your clarifications.

Best Regards,
Negara