From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Dan Magenheimer" <dan.magenheimer@oracle.com>
Subject: RE: Xen system skew MUCH worse than tsc skew (was RE:
	RE: [PATCH] record max stime skew (was RE: [PATCH] strictly
	increasinghvm guest time))
Date: Sat, 12 Jul 2008 15:05:45 -0600
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To: Ian Pratt <Ian.Pratt@eu.citrix.com>, Keir Fraser <Keir.Fraser@eu.citrix.com>, "Xen-Devel (E-mail)" <xen-devel@lists.xensource.com>
Cc: Dave Winchell <dwinchell@virtualiron.com>
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> Some NUMA systems have different oscillators on each node so you can't
> rely on the frequency being identical. Such systems are fairly rare
> (though their common use case is server virtualization). I guess a
> command line option to enable independent calibration for =

> these systems
> would be OK, though it would obviously be better to start off assuming
> the frequencies are identical, and then detect rate differences. =

> =

> Ian

Good point.  This is the way that Linux does it too, I think.

Dan