From owner-freebsd-smp  Sun Dec 29 23:33:11 1996
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To: brian@mediacity.com
cc: freebsd-smp@freebsd.org
Subject: Re: A question of how much memory? 
In-reply-to: Your message of "Sun, 29 Dec 1996 18:44:28 PST."
             <19961230024428.26653.qmail@mediacity.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Sun, 29 Dec 1996 23:33:07 -0800
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>David Greenman wrote:
>>    You're correct that your assumption is wrong. All of the memory is shared
>> in SMP PCs. The reason the machine panics is because you have run out of
>> kernel virtual memory. You need to more carefully tune the various parameters
>> in your kernel config file (the ones that take lots of virtual memory like
>> NMBCLUSTERS). The fact that it doesn't panic with 128MB indicates that you
>> are right on the edge of running out and the extra kernel data structures
>> that are allocated to manage 256MB is just enough to run out.
>
>>    BTW, why do you have bounce buffers configured in your kernel??
>
>That option is turned on in the GENERIC config by default.  Shall
>I comment it out?

   If you aren't using a ahc-1542 controller then you don't need it and it
just wastes kernel VM, so yes, comment it out.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project