From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Avi Kivity <avi@redhat.com>
Cc: Glauber Costa <glommer@redhat.com>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Marcelo Tosatti <mtosatti@redhat.com>,
Zachary Amsden <zamsden@redhat.com>,
"Xen-devel@lists.xensource.com" <Xen-devel@lists.xensource.com>
Subject: Re: [PATCH 1/5] Add a global synchronization point for pvclock
Date: Tue, 26 Oct 2010 10:04:38 -0700 [thread overview]
Message-ID: <4CC70A26.2090200@goop.org> (raw)
In-Reply-To: <4CC68DE1.1060604@redhat.com>
On 10/26/2010 01:14 AM, Avi Kivity wrote:
> On 10/26/2010 01:30 AM, Jeremy Fitzhardinge wrote:
>> Unfortunately this is breaking Xen save/restore: if you restore on a
>> host which was booted more recently than the save host, causing the
>> system time to be smaller. The effect is that the domain's time leaps
>> forward to a fixed point, and stays there until the host catches up to
>> the source host...
>
> Shouldn't save/restore also save the timebase?
Xen doesn't guarantee the system time is monotonic across those kinds of
events. The domain could maintain its own offset to maintain an
illusion of monotonicity, but I think its simpler to just zero
last_value on resume.
J
prev parent reply other threads:[~2010-10-26 17:04 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-15 18:37 [PATCH 0/5] pv clock misc fixes Glauber Costa
2010-04-15 18:37 ` [PATCH 1/5] Add a global synchronization point for pvclock Glauber Costa
2010-04-15 18:37 ` [PATCH 2/5] change msr numbers for kvmclock Glauber Costa
2010-04-15 18:37 ` [PATCH 3/5] Try using new kvm clock msrs Glauber Costa
2010-04-15 18:37 ` [PATCH 4/5] export new cpuid KVM_CAP Glauber Costa
2010-04-15 18:37 ` [PATCH 5/5] add documentation about kvmclock Glauber Costa
2010-04-15 19:28 ` Randy Dunlap
2010-04-15 20:10 ` Glauber Costa
2010-04-17 18:58 ` [PATCH 4/5] export new cpuid KVM_CAP Avi Kivity
2010-04-19 14:50 ` Glauber Costa
2010-04-20 9:29 ` Avi Kivity
2010-04-17 18:55 ` [PATCH 3/5] Try using new kvm clock msrs Avi Kivity
2010-04-17 18:51 ` [PATCH 2/5] change msr numbers for kvmclock Avi Kivity
2010-04-16 20:23 ` [PATCH 1/5] Add a global synchronization point for pvclock Marcelo Tosatti
2010-04-16 20:36 ` Jeremy Fitzhardinge
2010-04-16 21:05 ` Zachary Amsden
2010-04-19 10:39 ` Peter Zijlstra
2010-04-19 10:50 ` Avi Kivity
2010-04-19 11:05 ` Peter Zijlstra
2010-04-19 11:10 ` Avi Kivity
2010-04-19 14:21 ` Glauber Costa
2010-04-19 14:33 ` Avi Kivity
2010-04-19 14:46 ` Peter Zijlstra
2010-04-19 16:18 ` Jeremy Fitzhardinge
2010-04-20 9:31 ` Avi Kivity
2010-04-20 18:23 ` Jeremy Fitzhardinge
2010-04-20 18:54 ` Avi Kivity
2010-04-20 19:42 ` Jeremy Fitzhardinge
2010-04-21 0:07 ` Zachary Amsden
2010-04-22 13:11 ` Glauber Costa
2010-04-23 1:44 ` Zachary Amsden
2010-04-23 9:34 ` Avi Kivity
2010-04-23 19:22 ` Jeremy Fitzhardinge
2010-04-23 19:25 ` Avi Kivity
2010-04-23 21:31 ` Zachary Amsden
2010-04-23 21:35 ` Jeremy Fitzhardinge
2010-04-23 21:41 ` Zachary Amsden
2010-04-24 9:30 ` Avi Kivity
2010-04-24 9:29 ` Avi Kivity
2010-04-19 16:11 ` Jeremy Fitzhardinge
2010-04-19 14:26 ` Glauber Costa
2010-04-19 16:19 ` Jeremy Fitzhardinge
2010-04-19 18:25 ` Glauber Costa
2010-04-20 1:57 ` Marcelo Tosatti
2010-04-20 9:35 ` Avi Kivity
2010-04-20 12:59 ` Glauber Costa
2010-04-20 15:16 ` Avi Kivity
2010-04-21 0:01 ` Zachary Amsden
2010-04-21 8:06 ` Avi Kivity
2010-04-17 18:48 ` Avi Kivity
2010-04-17 18:49 ` Avi Kivity
2010-04-19 10:43 ` Peter Zijlstra
2010-04-19 10:47 ` Avi Kivity
2010-04-19 10:56 ` Peter Zijlstra
2010-04-19 11:13 ` Avi Kivity
2010-04-19 11:19 ` Peter Zijlstra
2010-04-19 11:40 ` Avi Kivity
2010-04-19 14:32 ` Glauber Costa
2010-04-19 14:37 ` Avi Kivity
2010-04-19 10:46 ` Peter Zijlstra
2010-04-19 10:49 ` Avi Kivity
2010-04-19 10:51 ` Peter Zijlstra
2010-04-19 10:54 ` Avi Kivity
2010-04-19 18:35 ` Zachary Amsden
2010-04-20 9:39 ` Avi Kivity
2010-04-21 0:05 ` Zachary Amsden
2010-04-21 8:08 ` Avi Kivity
2010-04-19 10:49 ` Peter Zijlstra
2010-04-19 10:53 ` Avi Kivity
2010-04-19 10:59 ` Peter Zijlstra
2010-04-19 11:35 ` Avi Kivity
2010-10-25 23:30 ` Jeremy Fitzhardinge
2010-10-26 8:14 ` Avi Kivity
2010-10-26 10:49 ` Glauber Costa
2010-10-26 17:04 ` Jeremy Fitzhardinge [this message]
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