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RE: [Xen-devel] clock drift in Xen 4.0.0

> From: Keir Fraser [mailto:keir.fraser@xxxxxxxxxxxxx]
> Subject: Re: [Xen-devel] clock drift in Xen 4.0.0
> >> Are you running NTP? 100ppm drift isn't unbelievable without
> external
> >> synchronisation.
> >
> > That's 7 minutes in front of the Dom0 that it's sitting on. The Dom0
> > runs ntp. Another DomU on the same system is ahead by a similar
> amount
> > (9 minutes over 74 days). I thought that with independent_wallclock=0
> > that they should stay in step.
> >
> > I actually just noticed that I'm running 4.0.0-rc6, not 4.0.0
> proper...
> > d'oh. I think I should probably update before thinking about it much
> > more.
> It probably depends on your dom0 and domU kernels also. Have they both
> been
> observed to behave 'properly' before? In particular I'm not sure pv_ops
> behaves same as ealrier kernels.

James --

"DomU" may imply PV but just to verify is this a PV domain or HV?

If an HV, Keir, didn't the default timer_mode change in 4.0?

Also, if HV, isn't independent_wallclock ignored?

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