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Date: Tue, 4 Jun 1996 15:25:10 -0700
From: Sean Eric Fagan <sef@kithrup.com>
Message-Id: <199606042225.PAA15769@kithrup.com>
To: smp@freebsd.org
Subject: Re: Unix/NT synchronization model (was: SMP progress?) 
Newsgroups: kithrup.freebsd.smp
In-Reply-To: <1827.833925902.kithrup.freebsd.smp@critter.tfs.com>
References: Your message of "Tue, 04 Jun 1996 15:00:44 PDT."
             <199606042200.PAA23901@MindBender.HeadCandy.com> 
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In article <1827.833925902.kithrup.freebsd.smp@critter.tfs.com> you write:
>Reply-to: phk@freebsd.org
>As in "I expect your guys to know this before you even try it ?"
>
>Frankly, we havn't spent much time seriously persuing this issue.

Well, that's not *quite* true ;).

Right now, it's going for extremely low-grained MP support -- only one
processor can be in kernel mode at a time.  If/when the secondary
processor(s) can take an interrupt, it will probably have reached that goal,
and will manage to improve performance.

Okay, so that's an extremely short-ranged goal ;).  But I don't expect true
symmetric MP to be happening for quite some time yet -- there's just too
much that would have to be changed.  (Locks around nearly every structure
reference in the kernel, for example.)

Sean.