This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] Time goes backwards in dom0 in xen-unstable

To: Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>, "Xen-Devel (E-mail)" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Time goes backwards in dom0 in xen-unstable
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Wed, 15 Apr 2009 08:30:37 +0100
Delivery-date: Wed, 15 Apr 2009 00:31:15 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <2bd706d8-59aa-440f-b38c-ad63523d3eab@default>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: Acm9OHn+WCSLB+0iSZOXf7o8w1bhcwAY5fvL
Thread-topic: [Xen-devel] Time goes backwards in dom0 in xen-unstable
User-agent: Microsoft-Entourage/
On 14/04/2009 20:36, "Dan Magenheimer" <dan.magenheimer@xxxxxxxxxx> wrote:

> I'm seeing some "Time went backwards" errors reported
> in dom0 in near-tip (c/s 19515) xen-unstable build.
> It's rare and random and not reproducible, but here's
> the report that just showed up.  There was no load
> running at the time.
> I can move to 3.4-rc1 if that would be helpful but I
> don't remember seeing any time-related changes recently.
> This was on my dual-core test machine which reports
> lots of power management info during Xen boot.

If you specify 'cpuidle=off' as a Xen boot parameter, does that make the
timer_interrupt scalability problem go away, and this time backwards
problem? I was going to enable by default in 3.4 but could go the other way.

 -- Keir

Xen-devel mailing list