Re: [PATCH] Updated: Dynamic Tick version 050408-1 - C-state measures

From: Pavel Machek
Date: Wed Apr 20 2005 - 07:00:44 EST


Hi!

> > Because I don't consider whether there was bm_activity the last ms, I only
> > consider the average, it seems to happen that I try to trigger
> > C3/C4 when there is just something copied and some bm active ?!?
>
> I don't think that this is perfect behaviour: if the system is idle, and
> there is _currently_ bus master activity, the CPU should be put into C1 or
> C2 type sleep. If you select C3 and actually enter it, you're risking
> DMA issues, AFAICS.

What kinds of DMA issues? Waiting 32msec or so is only heuristic; it
can go wrong any time. It would be really bad if it corrupted data or
something like that.
Pavel

--
Boycott Kodak -- for their patent abuse against Java.
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