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Date: Thu, 10 Jan 2013 07:42:44 +0700
From: Erich Dollansky <erichsfreebsdlist@alogt.com>
To: Michael Sierchio <kudzu@tenebras.com>
Subject: Re: To SMP or not to SMP
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Hi,

On Wed, 9 Jan 2013 16:25:41 -0800
Michael Sierchio <kudzu@tenebras.com> wrote:

> On Wed, Jan 9, 2013 at 4:18 PM, Erich Dollansky
> <erichsfreebsdlist@alogt.com> wrote:
> 
> > SMP goes into the applications. A single-CPU kernel must still run
> > these kind of applications.
> 
> Applications may be multithreaded - and on a host with more than one
> (real or virtual) CPU, those threads may run concurrently.  De quoi
> s'agit-il? What's your point?

they call those OS functions to handle mutexes etc. Some of these things
can be simpler when only a single CPU is present. I do not know if
there is a difference in FreeBSD.

With other words, it is a bit more complex than just an if instruction
in the kernel to decide what should be done. This is the reason why the
decision is made at compile time and not at run time.

Erich
> 
> - M
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