From: Andy Johnson <asjohn1@my-deja.com>
Subject: Re: 8i/Semaphore/Memory/Linux
Date: 2000/08/08
Message-ID: <8mnutp$68l$1@nnrp1.deja.com>#1/1
References: <gfGh5.70928$i5.1131296@news1.frmt1.sfba.home.com>
X-Http-Proxy: 1.0 x60.deja.com:80 (Squid/1.1.22) for client 206.160.4.144
Organization: Deja.com - Before you buy.
X-Article-Creation-Date: Tue Aug 08 03:31:04 2000 GMT
X-MyDeja-Info: XMYDJUIDasjohn1
Newsgroups: comp.databases.oracle.server
X-Http-User-Agent: Mozilla/4.73 [en] (X11; U; Linux 2.2.13 i586)


It's not obvious, but SHMMAX is the "max seg size" entry, which is 32
megs.  The 16 gig limit is the SHMMNI*SHMMAX.  So, SHMMAX needs to be
bumped up.  It says to use half of RAM, but on a machine with a lot of
RAM (more than a gig), you could go further.

Andy Johnson

In article <gfGh5.70928$i5.1131296@news1.frmt1.sfba.home.com>,
  Will Clements <whc2u@leptonics.com> wrote:
> 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
>

--
Do not confuse education with intelligence.
The presence of one does not imply the other.


Sent via Deja.com http://www.deja.com/
Before you buy.