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Re: [Xen-devel] Re: Fix for get_s_time()

To: Dave Winchell <dwinchell@xxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Re: Fix for get_s_time()
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Thu, 24 Apr 2008 17:37:04 +0100
Cc: "Tian, Kevin" <kevin.tian@xxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Ian Pratt <Ian.Pratt@xxxxxxxxxxxxx>, "dan.magenheimer@xxxxxxxxxx" <dan.magenheimer@xxxxxxxxxx>
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On 24/4/08 17:04, "Dave Winchell" <dwinchell@xxxxxxxxxxxxxxx> wrote:

> yes, this is the issue. What you suggest should be fine and I am trying
> it now.
> With the locking version (and a fix to a bug I introduced) I got .0012%
> error
> on an overnight run with hpet layered on get_s_time_mono(), which is the
> max(prev, cur) layer on get_s_time we discussed.

12 parts per million is pretty good. Is that cumulative deviation from 'wall
time' over ~12 hours? That could easily be explained by the fact that Xen
system time is not sync'ed with ntp.

 -- Keir

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