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Date: Wed, 25 Jan 2006 11:09:27 +0100
From: Alexander Leidinger <Alexander@Leidinger.net>
To: Poul-Henning Kamp <phk@phk.freebsd.dk>
References: <23570.1138137045@critter.freebsd.dk>
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Cc: arch@freebsd.org, current@freebsd.org
Subject: Re: [TEST/REVIEW] CPU accounting patches
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Poul-Henning Kamp <phk@phk.freebsd.dk> wrote:

[first patch]
> Of course, the scheme used in this patch suffers a bit if the
> hardware counter changes to other hardware of a different rate
> or simply changes rate.


[second patch]
> The downside is, that unless your cpu clock is correctly probed
> at boot and stays constant, your cpu accounting numbers will have
> a bogus scaling factor.

> For i386 and amd64 things are more tricky.  Laptops doing power
> saving tricks will probably give bogus cpu accounting values,
> but as such the patch should do no other harm than screw up
> those values.

Are you going to fix those issues for machines which do power saving tricks
(which may even be useful on servers for some people, not only on laptops),
or do you not intend to further work on this besides the patches you present
here?

Bye,
Alexander.

-- 
http://www.Leidinger.net  Alexander @ Leidinger.net: PGP ID = B0063FE7
http://www.FreeBSD.org     netchild @ FreeBSD.org  : PGP ID = 72077137
One man tells a falsehood, a hundred repeat it as true.