topic ORA-07279: spcre: semget error, unable to get first semaphore set. in Operating System - HP-UX

ORA-07279: spcre: semget error, unable to get first semaphore set.

Luca Frigatti — Tue, 04 Sep 2001 15:52:54 GMT

I get this error from ORACLE 7.2.3 on HP-UX 10.20.

I had 8 oracle instance already running on my server.

Somebody knows how to solve my problem?

Thanks in advance.

Regards.

Re: ORA-07279: spcre: semget error, unable to get first semaphore set.

Joseph C. Denman — Tue, 04 Sep 2001 16:02:30 GMT

You have run out of semaphores. You will need to shutdown one of the instances, or increase the kernal parms. There are numerous threads on kernal parms required by oracle.

...jcd...

Re: ORA-07279: spcre: semget error, unable to get first semaphore set.

CHRIS_ANORUO — Tue, 04 Sep 2001 16:05:05 GMT

Increase Shmmax from the kernel parameter set up, you can also look at the semaphores with ipcs -sobm

Re: ORA-07279: spcre: semget error, unable to get first semaphore set.

Rita C Workman — Tue, 04 Sep 2001 16:09:33 GMT

If you have other oracle instances running, they may be using the semmaphores. You may want to run and monitor how your semms are being hit:
sar -mS 1 300 will run every second for 5 minutes

Now this will help you - but the biggest and most important thing would be to take a look at all your oracle(s) ~init.ora files for the number of processes it requires. Then, as they say, do the math to set up your semms parms accordingly for all your oracle needs. Here's a thread that may help you a little..
http://forums.itrc.hp.com/cm/QuestionAnswer/1,1150,0x10ca6af52b04d5118fef0090279cd0f9,00.html

Regards,
Rita

Re: ORA-07279: spcre: semget error, unable to get first semaphore set.

Sridhar Bhaskarla — Tue, 04 Sep 2001 16:11:54 GMT

You need to consider two kernel parameters

semmni - Systemwide semaphores and
semmns - user accessable semaphores

You need to rebuild the kernel and reboot.

Do a sar -m 1 5 and if you see sema/s less than it's limit, then you need to increase only semmns. Otherwise you need to increase both semmni and semmns.

-Sri

Re: ORA-07279: spcre: semget error, unable to get first semaphore set.

Magdi KAMAL — Wed, 05 Sep 2001 12:00:51 GMT

Hi Luca,

For 8 oracle instances, you have to INCREASE your unix system kernel parameters :
semaem
semmap
semmni
semmns
semmnu
semume
semvmx : if needed.

Magdi

Re: ORA-07279: spcre: semget error, unable to get first semaphore set.

Sanjay_6 — Wed, 05 Sep 2001 22:58:16 GMT

Hi,

You can also tune nflock. The Oracle Manual says

//Begin//

The kernel parameter nflocks defines the maximum number of file locks available on the system. The recommended setting for nflocks is

nflocks = 200 + sum of the values of init.ora parameter db_files for all instances of oracle on the machine.

Hope this helps

Thanks