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] [timer/ticks related] dom0 hang during boot on large 1TB

To: Jan Beulich <JBeulich@xxxxxxxxxx>, Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>, "mukesh.rathor@xxxxxxxxxx" <mukesh.rathor@xxxxxxxxxx>
Subject: Re: [Xen-devel] [timer/ticks related] dom0 hang during boot on large 1TB system
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Tue, 22 Dec 2009 13:35:24 +0000
Cc: "kurt.hackel@xxxxxxxxxx" <kurt.hackel@xxxxxxxxxx>, Jeremy Fitzhardinge <jeremy@xxxxxxxx>, "Xen-devel@xxxxxxxxxxxxxxxxxxx" <Xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Tue, 22 Dec 2009 05:35:52 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4B30B721020000780002726C@xxxxxxxxxxxxxxxxxx>
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: AcqC91RhXCH5M+CIRj2rencMce1MhQAFEjkA
Thread-topic: [Xen-devel] [timer/ticks related] dom0 hang during boot on large 1TB system
User-agent: Microsoft-Entourage/
On 22/12/2009 11:10, "Jan Beulich" <JBeulich@xxxxxxxxxx> wrote:

> Nevertheless I remain convinced that the problem ought not to be fixed
> by a kernel change (and even less by one that modifies Xen-unspecific
> code). Any patch to this effect, unless I should be convinced otherwise,
> has my explicit up front NAK (in case this counts anything).

Well, I must say the kernel patch looked quite sensible to me. If no other
reason than reinforcing the fact that jiffy values should always be compared
using the provided macros. But I'm happy to have a hypervisor patch as well,
if we can work out what it should be. I'm still unclear on the reason why
slow page scrubbing causes this problem - Oracle's explanation hasn't
convinced me yet.

> And then it should be possible to simulate the problem quite easily on
> a system with much less memory, by slowing down the scrub loop
> artificially. If I find time before the holiday break I'll try to do that and
> see if I can convince myself otherwise (as per above).
> artificially

That would be helpful, thanks. I'm particularly intrigued by how this could
be seen for dom0 but not be a similar or worse issue for domU.

 -- Keir

Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>