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Subject: Re: [STATUS 2.5]  July 10, 2002
To: cort@fsmlabs.com (Cort Dougan)
Date: Wed, 10 Jul 2002 22:07:12 +0100 (BST)
Cc: rml@tech9.net (Robert Love), vherva@niksula.hut.fi (Ville Herva),
       linux-kernel@vger.kernel.org
In-Reply-To: <20020710142005.U762@host110.fsmlabs.com> from "Cort Dougan" at Jul 10, 2002 02:20:05 PM
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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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> Why was the rate incremented to maintain interactive performance?  Wasn't
> that the whole idea of the pre-empt work?  Does the burden of pre-empt
> actually require this?

Bizarrely in many cases it increases throughput

> It seems that the added inefficiency of these extra interrupts is going to
> drag performance down.

Sometimes - Beowulf folks already sometimes hack the clock down to 20Hz or
less. This is best approached on sane hardware by extending the S/390 stuff
for no regular ticks.

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