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Date: Mon, 06 Dec 2010 20:56:32 +0200
From: Andriy Gapon <avg@freebsd.org>
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To: Jung-uk Kim <jkim@freebsd.org>
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Cc: freebsd-current@freebsd.org
Subject: Re: non-invariant tsc and cputicker
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on 06/12/2010 20:34 Jung-uk Kim said the following:
> I understand that.  However, it is not clear to me why you want to 
> pessimize performance of old hardware.  If you can convince me old 
> hardware with slow timecounter hardware (e.g., i8254) does not hurt 
> too much, maybe it's okay.

Overlooked this point - TSC can be very well used as a timecounter.
And in that case non-invariant TSC would veto P-state changes, which is the proper
thing to do, IMO.

-- 
Andriy Gapon