From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: SMP kernels on single processor machines
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Marius Groeger <mgroeger@sysgo.com>
Cc: Lee Braiden <lee_b@member.fsf.org>,
	"debian-powerpc@lists.debian.org" <debian-powerpc@lists.debian.org>,
	linuxppc-dev list <linuxppc-dev@lists.linuxppc.org>
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Date: Sat, 22 May 2004 09:11:26 +1000
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On Fri, 2004-05-21 at 22:58, Marius Groeger wrote:

> FWIW, CONFIG_PREEMPT _does_ reduce the avarage scheduling latency.
> It's still sort of soft real-time, but the effect is measurable (I'm
> talking 2.4 kernels here, BTW) However, on desktop systems you
> probably don need to worry about this, but for an embedded system you
> may like the slightly improved reaction time.

Well... average latency is mostly meaningless, only peak latency really
matters for anything that need some sort of real time imho...

Ben.


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