Re: Clock issue in Windows XP guests

[Zachary Amsden <zamsden@redhat.com>]

On 03/03/2010 11:43 PM, Gilles PIETRI wrote:
> Hi,
>
> I have a host running a 2.6.32.7 kernel, and I'm using qemu-kvm 
> 0.12.2. I have multiple guests, and one of them is running Windows XP. 
> If I stare at the clock, I see that every now & then (~5s), it slows 
> down a bit, and then try to cope with it. If I run some NTP 
> synchronization software like ntpd, the offset is as high as 1s lost 
> every 10s or so, which makes it impossible to use anything time based 
> on the guest (audio stuff, mainly).
>
> I tried messing (as said on IRC) with the -rtc parameters, but to no 
> avail. I tried the driftfix=slew option found in the --help output, 
> but it says that driftfix is not a valid setting for rtc.. And anyway, 
> I have no idea what this does (I'll be reading about it probably...)
>
> I've seen something remotely connected to this on the proxmox forum, 
> but it was not that helpful (and proxmox runs qemu 0.11.x as it seems):
> http://forum.proxmox.com/threads/2050-Slow-clock-time-drift-in-windows-guests?p=17962 
>
>
> I remember using the -rtc-td-hack (and in fact, just read again about 
> it here: 
> http://forum.proxmox.com/threads/2381-Recommended-clock-source-for-KVM-guests), 
> but it's not there anymore in 0.12.x, and I have no idea what it used 
> to do (going on for some reading as well, when I have some time ;))
>
> Oh, and the guests running linux are working just fine, and have no 
> clock issue.
>
> Has anyone encountered such a problem?

No, but I'd certainly like to fix it.  Can you send basic host 
information like /proc/cpuinfo, dmesg from kernel?

If you run the one Windows XP guest alone, does it run better or still 
the same?

Thanks,

Zach