8i/Semaphore/Memory/Linux

From: Will Clements <whc2u_at_leptonics.com>
Date: 2000/08/01
Message-ID: <gfGh5.70928$i5.1131296@news1.frmt1.sfba.home.com>#1/1

Hi ALL,

Trying to get an idea of what the Linux kernel configuration parameters should be for a medium sized implementation of Oracle 8i. I've already installed Oracle 8.1.6 EE for linux on the stock RedHat 6.2 a few times with no problems.

The Oracle documentations recommends:

 SHMMAX (0.5*physical memory)
 SHMMIN 1
 SHMMNI 100
 SHMSEG 10

 SEMMSL   (10 + largest process parameter)
          (Default process pramaeter = 50)
 SEMMNS   (set formula)

 SEMOPM 100
 SEMVMX 32767 Stock RedHat 6.2 (result of "ipcs -l" command):

• Shared Memory Limits -------- max number of segments = 128 max seg size (kbytes) = 32768 max total shared memory (kbytes) = 16777216 min seg size (bytes) = 1
• Semaphore Limits -------- max number of arrays = 128 max semaphores per array = 250 max semaphores system wide = 32000 max ops per semop call = 32 semaphore max value = 32767
• Messages: Limits -------- max queues system wide = 128 max size of message (bytes) = 4056 default max size of queue (bytes) = 16384

My interpretation of the RedHat defaults:

 SHMMAX 16,777,216 KB
 SHMMIN 1
 SHMMNI 128
 SHMSEG 128
 SEMMSL 250
 SEMMNS 320000 (SEMMNI*SEMMSL)
 SEMOPM 32
 SEMVMX 32767 Now according to this, really, the only thing I need to change is SEMOPM. Is this correct? But I'm wondering if I will encounter trouble if SEMMNS and SHMMAX are set this high. Any thoughts on this before I recompile the Linux kernel? (I'm also switching to kernel version 2.2.16).

Will Cl Received on Tue Aug 01 2000 - 00:00:00 CDT