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Date: Fri, 06 Sep 1996 11:05:37 -0400
To: freebsd-questions@FreeBSD.ORG
From: Rob Miracle <rwm@MPGN.COM>
Subject: SYSV Shared Memory Question
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We need a boat load of SYSV shared memory and we get a Kernel panic when we
try to request it.  Here are the specifics:

PentiumPro 200, 256M memory
We need 22000 pages of Shared memory for one application, and a little bit
more.  On Ultrix 4.4, we declare smmax at 24000 and smseg 32 and things work
well.  The total shared memory can be any amount.

On our FreeBSD 2.x.x (we have tried 2.1.0, 2.1.5, and 2.2.snap (most recent))
when we set SHMMAXPGS to 22000 and SHMALL to something over 30000, we get a
kernel panic in kmem_suballoc of type 3.

My questions are:

Is there a limit to the amount of SYSV shared memory in FreeBSD(any version)?
What are the real meanings of SHMMAXPGS, SHMALL, SHMMAX, and other shared memory
options?

We really want to move away from our DecStations and move to PCs but this is
a big sticky issue.

Any other pointers?

Thanks
Rob

--
Rob Miracle <rwm@TanSoft.com>
Tantalus Inc.
Be patient or be a patient. -- Anton Devious