Re: SUN4, IPCS, two instances,....H.E.L.P!!
Date: 18 May 1993 13:04:47 +0200
Message-ID: <1tafsf$e0o_at_hdxu03.telecom.ptt.nl>
In article <30896_at_suned1.Nswses.Navy.MIL> lev_at_ipxed5.nswses.navy.mil (Lloyd E Vancil) writes:
>number of semaphores....
>Take oracle 6 off line and oracle 7 plays..
>
>ipcs -s returned:
>
>IPC status from spcsed3 as of Mon May 17 14:56:08 1993
>T ID KEY MODE OWNER GROUP
>Semaphores:
>s 20 0x00000000 --ra-r----- oracle dba
>Question. Is oracle grabbing all of the available
>semaphores?
I don't know about this one, but you can get a better idea on the semaphore with
ipcs -a
In the section semaphores you will see a column NSEMS (At least on my machine:
HPux 8.0..). This is the number of semaphores that oracle requested.
>Question. Where can I find info about the default
>values for semmnu, semume, semmns and semmni?
In the installation guide are some default values described but not for 'strange' situation. In my situation I have to run 10 to 15 instances.
>Question. What is the method for determining the optimum values
>for these parameters?
>
Oracle takes per instance one semaphore map. The kernel parameter for this is
(in SVR4: SEMMNI). With SEMMNI on 25 you can get about 20 instances running.
Per semaphore map oracle takes one semaphore per process it is running. So 4
for the regular plus the PROCESS variable in the init??.ora. This kernel
variable is: SEMMSL (40 is a good choice, at least in my situation)
The last variable you've got to change is the system wide nr of semaphores
available: SEMMNS (set this as high as posible, approx 500-600, for a lot of
instances and a lot of processes).
>Question. Is there anyone out there?
>
If you read this: YES
I hope you got a few answers on your questions
Peter
Peter van der Kooi | Telephone: +31 50 855459 PTT Telecom BV | Telefax : +31 50 855310 I&AT | E-mail : peter%ptt-iat_at_nluug.nl P.O. Box 188 | DISCLAIMER: This statement is not an official NL-9700 AD Groningen | statement from, nor does it represent and The Netherlands | official position of, PTT Telecom B.V. --------------------------------------------------------------------------------Received on Tue May 18 1993 - 13:04:47 CEST