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Date: Tue, 18 Jun 2002 14:23:37 -0300 (BRT)
From: Rik van Riel <riel@conectiva.com.br>
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To: Chris Friesen <cfriesen@nortelnetworks.com>
Cc: David Schwartz <davids@webmaster.com>, <rml@tech9.net>, <mgix@mgix.com>,
       <linux-kernel@vger.kernel.org>
Subject: Re: Question about sched_yield()
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On Tue, 18 Jun 2002, Chris Friesen wrote:

> >         It has to. What if the only task running is:
> >
> >         while(1) sched_yield();
> >
> >         What would you expect?
>
> If there is only the one task, then sure it's going to be 100% cpu on
> that task.
>
> However, if there is anything else other than the idle task that wants
> to run, then it should run until it exhausts its timeslice.
>
> One process looping on sched_yield() and another one doing calculations
> should result in almost the entire system being devoted to calculations.

So if you have a database with 20 threads yielding to each other
each time a lock is contended and one CPU hog the database should
be reduced to a very small percentage of the CPU ?

regards,

Rik
-- 
	http://www.linuxsymposium.org/2002/
"You're one of those condescending OLS attendants"
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