From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Latest unstable detects cpu speed incorrectly
Date: Tue, 27 Oct 2009 15:31:45 -0700
Message-ID: <4AE774D1.2080907@goop.org>
References: <09ba61b1-d916-482c-ad37-1433375f9d87@default>
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To: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: xen-devel@lists.xensource.com, Valtteri Kiviniemi <valtteri.kiviniemi@dataproof.fi>, Keir Fraser <keir.fraser@eu.citrix.com>
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On 10/27/09 15:15, Dan Magenheimer wrote:
> The downside is
> of course is that the extra multiply would need to be
> done on every emulated TSC (unless maybe it could be folded
> into the other required scaling?)
>   

Given the speed of multipliers compared to everything else on the
emulation path, I don't think it would be measurable let alone
noticeable (my measurements show that multiply is trivial compared to a
native rdtsc).

The nice thing about a fixed 1GHz emulated tsc is that it makes it clear
that it is emulated.

    J