From: Con Kolivas <kernel@kolivas.org>
To: "Tetsuji \"Maverick\" Rai" <tetsuji.rai@gmail.com>
Subject: Re: HT scheduler: is it really correct? or is it feature of HT?
Date: Thu, 19 May 2005 17:18:55 +1000
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On Thu, 19 May 2005 04:58 pm, Tetsuji "Maverick" Rai wrote:
> On 5/19/05, Con Kolivas <kernel@kolivas.org> wrote:
> > ------------snip---------------
> > Hyperthread sibling cpus share cpu power. If you let a nice 19 task run
> > full power on the sibling cpu of a nice 0 task it will drain performance
> > from the nice 0 task and make it run approximately 40% slower. The only
> > way around this is to temporarily make the sibling run idle so that a
> > nice 0 task gets the appropriate proportion of cpu resources compared to
> > a nice 19 task. It is intentional and quite unique to the linux cpu
> > scheduler as far as I can tell. On any other scheduler or OS a nice 19
> > "background" task will make your machine run much slower.
> >
> Thanks.   I understood it's a feature of linux kernel and am satisfied
> with it.  Actually on Windows xp my application sometimes slows down
> maybe due to inpropoer scheduler.

Well I invented it so it's very unlikely that Windows* will have it (?yet) :D

Cheers,
Con
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