kmtune vs. sam

[Infra team member]

Hi folks,
OS=hpux 11.11 (bootet after new kernel gen.!!)

I tried to get all hosts in sync with the kernel parameters (same apps on all hosts) and for that I excecute following command:
#kmtune -q shmmax
Parameter Current Dyn Planned
=========================================
shmmax 67108864 Y (20*1024*1024*1024)

#kmtune -l
Parameter: shmmax
Current: 67108864
Planned: (20*1024*1024*1024)

SAM is showing the correct values.
shmmax 21474836480 21474836480 Dynamic N/A

btw. sam is showing the value but not the formula but when you like to change the value, the formule will shown.

Looks like that kmtune is not ok.
Any ideas?

Thanks in advance.
Klaus

[Steven E. Protter]

Shalom,

I don't think its a matter of kmtune being wrong.

You need to be in a certain directory and understand the entire process of putting a kernel into production to get accurate results from kmtune, or its successor kctune(11iv2).

Here is a guide.

#cd /stand
#cp vmunix vmunix.old
#cp system system.old
#cd build
#/usr/lbin/system/system_prep -s system

Edit system file and make changes here as per ur require ment. Imeand addition/Deletion of devices. Then
#mk_kernel -s system
For more information see the man page of mk_kernel

Now one new kernel will be created in /stand/buil directory. Copy this to original location
#cd /stan/build
#cp vmunix_test /stand/vmunix
#cp system /stand

Now reboot the system . In case rebuilding was not successfull, Boot thru /stand/vmunix.old and recover kernel.



From an ITRC thread.

SEP

[inventsekar_1]

http://docs.hp.com/en/TKP-90202/re87.html?btnNext=next%A0%BB

yes. looks something wrong with the kmtune.
kmtune -q shmmax gives hex value in my system.

kmtune -q shmmax
Parameter Current Dyn Planned Module Version
===============================================================================
shmmax 0x40000000 Y 0X40000000

[Bill Hassell]

Formulas (formulae?) are just a pain -- period. The value is all the kernel knows because the formula is evaluated as the kernel is built and does not remain in the finished kernel. It is part of the /stand/system file. So go to the systems where kmtune reports a formula and replace the formula with the desired value.

[Infra team member]

Thanks to all who respond.
At the end the answer from Bill Hassel was the solution/reality. Sorry Bill, you will get next time an additional 5 points bonus from me.

kmtune -s shmmax=21474836480 #set value planned
kmtune -q shmmax
Parameter Current Dyn Planned
=================================
shmmax 67108864 Y 21474836480

kmtune -u #set value current
kmtune -q shmmax
Parameter Current Dyn Planned
=================================
shmmax 21474836480 Y 21474836480


Thanks and regards,
Klaus