From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: Timedrift in KVM guests after livemigration.
Date: Mon, 19 Apr 2010 12:29:19 +0300
Message-ID: <20100419092919.GA10744@redhat.com>
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To: Espen Berg <espen@monsternett.no>
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On Mon, Apr 19, 2010 at 11:21:47AM +0200, Espen Berg wrote:
> Den 18.04.2010 11:56, skrev Gleb Natapov:
> 
> >>That's two different things here:
> >>The issue that Espen is reporting is that the hosts have different
> >>frequency and guests that relay on the tsc as a source clock will
> >>notice that post migration. The is indeed a problem that -tdf does
> >>not solve. -tdf only adds compensation for the RTC clock emulation.
> >>
> >It's -rtc-td-hack. -tdf does pit compensation, but since usually kernel
> >pit is used it does nothing.
> 
> So this "hack" will not solve our problem?
> 
If your guest uses RTC for time keeping it may help. Otherwise it does
nothing.

--
			Gleb.