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Date: Thu, 6 Dec 2001 14:35:16 -0800
From: Larry McVoy <lm@bitmover.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Larry McVoy <lm@bitmover.com>, "David S. Miller" <davem@redhat.com>,
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Subject: Re: SMP/cc Cluster description
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On Thu, Dec 06, 2001 at 10:37:18PM +0000, Alan Cox wrote:
> >    problem.  Scheduler, networking, device drivers, everything.  That's
> >    thousands of locks and uncountable bugs, not to mention the impact on
> >    uniprocessor performance.
> 
> Most of my block drivers in Linux have one lock. The block queuing layer
> has one lock which is often the same lock.

Hooray!  That's great and that's the way I'd like to keep it.  Do you think
you can do that on a 64 way SMP?  Not much chance, right?

> > You tell me - which is easier, multithreading the networking stack to 
> > 64 way SMP or running 64 distinct networking stacks?
> 
> Which is easier. Managing 64 routers or managing 1 router ?

That's a red herring, there are not 64 routers in either picture, there
are 64 ethernet interfaces in both pictures.  So let me rephrase the
question: given 64 ethernets, 64 CPUs, on one machine, what's easier,
1 multithreaded networking stack or 64 independent networking stacks?
-- 
---
Larry McVoy            	 lm at bitmover.com           http://www.bitmover.com/lm 
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