Subject: Re: xen 2: bogus microtime value
To: None <fukumoto@imasy.or.jp>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: port-xen
Date: 04/28/2007 21:36:42
On Sat, Apr 28, 2007 at 06:53:20PM +0900, fukumoto@imasy.or.jp wrote:
> I'm trying to setup xen 2, but having problem. One problem filed as
> kern/36188. To track the problem, I tried ktrace/kdump, and I noticed
> the timestamp of kdump -T is bogus. I looked into the
> sys/arch/xen/xen/clock.c, and apparently some offset attempt seems to
> be made when XEN_CLOCK_DEBUG is turned on. When I recompiled
> XEN2_DOM0 with XEN_CLOCK_DEBUG, dmesg is filled with "xen_microtime:
> unexpectedly large tv_usec 6445854" and so on.
>
> So, is this something expected, or bug? Kernel is netbsd-4, xenkernel
> is xen-2.0.7 from pkgsrc.
I don't remember the details exatly (I think they are in port-xen archives),
but I think the xen-2 hypervisor interface doesn't allow for precise
microtime support. Xen-3 is better in this area.
--
Manuel Bouyer <bouyer@antioche.eu.org>
NetBSD: 26 ans d'experience feront toujours la difference
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