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From: "Jorn Argelo" <jorn@wcborstel.nl>
To: "adp" <dap99@i-55.com>
Date: Thu, 16 Sep 2004 22:39:25 +0200
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cc: questions@freebsd.org
Subject: Re: SMP on SMP-capable system with one processor
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On Thu, 16 Sep 2004 13:09:22 -0500, adp wrote
> We have several Dell-based systems that are dual-processor capable,
>  but have only one processor. The FreeBSD 4.9 kernels for each 
> system is compiled with SMP support, even though there is only one 
> processor on each system right now.
> 
> Would this actually reduce performance on a single processor system? 
> I know that SMP kernels have to worry about special locking, and may 
> be doing unnecessary work.
> 

I don't think so. There are probably quite a few machines out there that run
the GENERIC kernel, which includes SMP support. Remember it's just support;
it's not required for the machine to function. Correct me if I'm wrong though.

Cheers,

Jorn