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Date: Wed, 5 Dec 2001 13:05:47 -0800
From: Larry McVoy <lm@bitmover.com>
To: "Martin J. Bligh" <Martin.Bligh@us.ibm.com>
Cc: Larry McVoy <lm@bitmover.com>, Rik van Riel <riel@conectiva.com.br>,
        Lars Brinkhoff <lars.spam@nocrew.org>,
        Alan Cox <alan@lxorguk.ukuu.org.uk>, hps@intermeta.de,
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Subject: Re: SMP/cc Cluster description [was Linux/Pro]
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> > What I am proposing is to cluster *OS* images on a *single* SMP as a way of
> > avoiding most of the locks necessary to scale up a single OS image on the 
> > same number of CPUs.
> 
> Which, to me, makes the whole thing much less interesting, since there aren't
> SMP systems about that are really large that I know of anyway. Scaling to 
> the size of current SMP systems is a much less difficult problem than scaling
> to the size of NUMA systems.

We don't agree on any of these points.  Scaling to a 16 way SMP pretty much 
ruins the source base, even when it is done by very careful people.

> The main advantage of starting with a single OS image, as I see it, is
> that you have a system that works fine, but performs badly, from the
> outset. 

Hey, I can make one of those :-)

Seriously, I went through this at SGI, that's exactly what they did, and it
was a huge mistake and it never worked.
-- 
---
Larry McVoy            	 lm at bitmover.com           http://www.bitmover.com/lm 
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