From owner-freebsd-smp  Wed Aug 27 07:16:18 1997
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To: Christopher Petrilli <petrilli@amber.org>
cc: Kyle Mestery <mestery@winternet.com>, Peter Stubbs <peters@gil.com.au>,
        smp@FreeBSD.ORG
Subject: Re: A how does it work question. 
In-reply-to: Your message of "Wed, 27 Aug 1997 10:07:20 EDT."
             <Pine.BSF.3.95q.970827100635.20292A-100000@chaos.amber.org> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Wed, 27 Aug 1997 07:18:30 -0700
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>Because of this, wouldn't it be appropriate to say that FreeBSD is an
>Assymetric MP, not Symmetric?  Symmetric means that the kernel runs on
>each processor, and there is no "one processor" which controls exclusivity
>to the hardware.

   No. FreeBSD's MP is symetric - either CPU may execute kernel code. The
issue has to do with concurrency and right now, only one CPU may execute
the code at one time. Asymetric MP is something different entirely - in
that case, only one CPU ever executes kernel code and it schedules the work
for the other CPUs.

-DG

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