From mboxrd@z Thu Jan  1 00:00:00 1970
From: Espen Berg <espen@monsternett.no>
Subject: Re: Timedrift in KVM guests after livemigration.
Date: Sat, 17 Apr 2010 21:52:04 +0200
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Den 15.04.2010 09:35, skrev Espen Berg:
> We have three KVM hosts that supports live-migration between them, but
> one of our problems is time drifting. The three frontends has different
> CPU frequency and the KVM guests adopt the frequency from the host
> machine where it was first started.
>
> Host1: cat /proc/cpuinfo
> model name : Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz
> cpu MHz : 2394.048
>
> Host2: cat /proc/cpuinfo
> model name : Intel(R) Core(TM)2 CPU 6700 @ 2.66GHz
> cpu MHz : 2659.685
>
> Host3: cat /proc/cpuinfo
> model name : Intel(R) Xeon(R) CPU E5410 @ 2.33GHz
> cpu MHz : 2327.507
>
>
> virsh version
> Compiled against library: libvir 0.7.6
> Using library: libvir 0.7.6
> Using API: QEMU 0.7.6
> Running hypervisor: QEMU 0.11.0
>
> Is there any solution to our problems, or is a reboot the only safe
> solution?

Is there no one with similar problems here? :\  Guess I should file a 
bug report or something if the same problems occur in the latest 
version.  I can't se any changes in change log after 0.11.x that relate 
to this problem.  We can't be the only one that uses different CPUs in a 
migration environment.

Since this is a cluster in production, I'm not able to try the latest 
version either.

Espen.