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From: Michal Mertl <mime@traveller.cz>
To: skylar@cs.earlham.edu
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Date: Thu, 31 Aug 2006 14:38:46 +0200
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Cc: backyard1454-bsd@yahoo.com, Jordi Carrillo <jordilin@gmail.com>,
	freebsd-questions@freebsd.org
Subject: Re: SMP detection
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Skylar Thompson wrote:
> Michal Mertl wrote:
> > No! Kernel threads (e.g. handling interrupts) aren't that much different
> > to normal processes.
> >
> > Logical CPUs on a single HTT capable CPU share most of the CPU logic,
> > especially all the external stuff (handling interrupts). Scheduling
> > handling of interrupts on the "secondary/logical" core  wouldn't
> > probably help performance at all (if that is at all possible).
> >   
> 
> Could you clarify note 20031022 in /usr/src/UPDATING? It states that HTT
> CPUs are used for interrupts if they are detected, even if they aren't
> used by regular processes. Was this something that just showed up in
> pre-6.x releases?
> 

I think it means that if an interrupt would for some reason be signalled
to the unused logical core it wouldn't be lost or something.

Michal