From: Keir Fraser <keir.fraser@eu.citrix.com>
To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>,
Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>,
Joanna Rutkowska <joanna@invisiblethingslab.com>,
Rafal Wojtczuk <rafal@invisiblethingslab.com>
Subject: Re: S3 sleep in dom0 breaks dom0<->domU wallclock synchronization
Date: Mon, 5 Jul 2010 20:26:42 +0100 [thread overview]
Message-ID: <C857F082.19737%keir.fraser@eu.citrix.com> (raw)
In-Reply-To: <4C322FF9.1050601@goop.org>
On 05/07/2010 20:18, "Jeremy Fitzhardinge" <jeremy@goop.org> wrote:
> So the problem is that dom0 does the S3 suspend/resume, and presumably
> its wallclock time is updated properly via Linux's normal mechanisms.
> But the S3 suspend/resume is unnoticed by all the domUs, so they don't
> know that an enormous amount of time has passed in an instant? Does
> that affect all the guest clocks, or just wallclock?
Um, just wallclock I think?
> How does Xen deal with the S3 suspend/resume? Does the system clock
> just keep ticking as usual (so the whole suspended time appears to be
> sub-nanosecond), but the wallclock offset gets updated?
This.
-- Keir
> Or does it try
> to workout how long the suspended time was and adjusts the system time
> accordingly? That would allow guest timekeeping to compensate for the
> suspended time, assuming they can deal with large forward leaps.
next prev parent reply other threads:[~2010-07-05 19:26 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-01 3:04 S3 sleep in dom0 breaks dom0<->domU wallclock synchronization Rafal Wojtczuk
2010-07-01 14:50 ` Keir Fraser
2010-07-01 14:51 ` Keir Fraser
2010-07-01 15:18 ` Joanna Rutkowska
2010-07-01 16:12 ` Keir Fraser
2010-07-05 19:18 ` Jeremy Fitzhardinge
2010-07-05 19:26 ` Keir Fraser [this message]
2010-07-05 22:43 ` Joanna Rutkowska
2010-07-05 22:50 ` Jeremy Fitzhardinge
2010-07-05 23:03 ` Joanna Rutkowska
2010-07-05 23:19 ` Jeremy Fitzhardinge
2010-07-06 9:12 ` Joanna Rutkowska
2010-07-06 16:17 ` Jeremy Fitzhardinge
2010-07-06 3:52 ` Keir Fraser
2010-07-06 9:10 ` Joanna Rutkowska
2010-07-06 10:02 ` Jan Beulich
2010-07-06 10:27 ` Joanna Rutkowska
2010-07-06 12:50 ` Keir Fraser
2010-07-06 14:09 ` Joanna Rutkowska
2010-07-08 14:06 ` Joanna Rutkowska
2010-07-06 14:53 ` Dan Magenheimer
2010-07-06 16:24 ` Jeremy Fitzhardinge
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