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From: jak@rudolph.ccur.com (Joe Korty)
Message-Id: <200203152159.VAA27831@rudolph.ccur.com>
Subject: Re: [PATCH] 2.4.18 scheduler bugs
To: mingo@elte.hu
Date: Fri, 15 Mar 2002 16:59:31 -0500 (EST)
Cc: alan@lxorguk.ukuu.org.uk (Alan Cox), joe.korty@ccur.com (Joe Korty),
        marcelo@conectiva.com.br (Marcelo Tosatti),
        torvalds@transmeta.com (Linus Torvalds), linux-kernel@vger.kernel.org
Reply-To: joe.korty@ccur.com (Joe Korty)
In-Reply-To: <Pine.LNX.4.44.0203152138550.22550-100000@elte.hu> from "Ingo Molnar" at Mar 15, 2002 09:42:33 PM
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> > [...] But on the Athlon the IPI isnt going down a little side channel
> > between cpus.
> 
> but even in the Athlon case an IPI is still an IRQ entry, which will add
> at least 200 cycles or more to the idle wakeup latency.

It is an idle cpu that is spending those 200 cycles.

Joe
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