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Subject: Re: Stolen and degraded time and schedulers
From: Daniel Walker <dwalker@mvista.com>
To: Jeremy Fitzhardinge <jeremy@goop.org>
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Date: Wed, 14 Mar 2007 09:11:13 -0700
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On Tue, 2007-03-13 at 23:52 -0700, Jeremy Fitzhardinge wrote:

> >
> > That's true, but given a constant clock (like what sched_clock should
> > have) then the accounting is similarly inaccurate. Any connection
> > between the scheduler and the TSC frequency changes aren't part of the
> > design AFAIK ..
> >   
> 
> Well, my whole argument is that sched_clock /should not/ be a constant
> clock.  And I'm not quite sure why you keep bringing up the tsc, because
> it has no relevance.

Then your direction is wrong, sched_clock() should be constant ideally
(1millisecond should really be 1millisecond). Like I said in the last
email, change the scheduler to make it aware of the variable quantum
values.

Daniel