semop: Invalid argument - Error log on HP-UX cluster

[Tiem Nguyen Van]

Dear all,
I have trouble with our HP-UX clustered system.
In the active node, the logfile keep loging that
"semop: Invalid argument" so the root volume growth very fast.
Any one know the error message meaning and how to
correct it ?

Many thanks.
Tiem NV

[Dietmar Konermann]

Well,

semop(2) is supposed to fail with "Invalid Argument", if... (see man 2 semop):

[EINVAL] semid is not a valid semaphore identifier.

[EINVAL] The number of individual semaphores for which the calling process requests a SEM_UNDO would exceed the limit.

I would suggest to look at the 2nd reason first... which means increasing kernel tunable "semume".

Best regards...
Dietmar.

[Tiem Nguyen Van]

Hi Dietmar,

Thanks for you respond.
The current semume of our system is : 10.
Do you think it reasonable?
Any other related Kernel parameter should be consider ?

Best regards,
Tiem NV

[Dietmar Konermann]

Hi Tiem NV,

well, 10 is the default setting on "older" HP-UX releases like 11.11. On 11.23 it's 100 now... guess, why. :-)

For futher explanations have a look at:
http://docs.hp.com/en/B3921-90010/semume.5.html

It's an online version of the 11iV2 man pages. They include man pages for each tunable also. Good to know, I think.

I'm unable to give general tunable suggestetions... sorry, but that depends on your applications and the load you are running on them.

Take care to prepare each of your cluster nodes to handle the sum of all package loads that *could* run simultaneously!

Best regards...
Dietmar.