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From: Avi Kivity <avi@redhat.com>
To: Prateek Sharma <prateek3.14@gmail.com>
Cc: kvm@vger.kernel.org
Subject: Re: KVMClock skew
Date: Wed, 07 Mar 2012 12:46:49 +0200	[thread overview]
Message-ID: <4F573C99.4060107@redhat.com> (raw)
In-Reply-To: <CAKwxwqz=GYtELgUdkHPcdOyO2O2qOU85tc361REL+oSoH7A0oQ@mail.gmail.com>

On 02/20/2012 11:14 AM, Prateek Sharma wrote:
>    Hello all,
> If i use KVMclock as the clock source in the guest, the guest clock
> 'lags behind' the host clock by a big margin (1 second or more). The
> time difference is not consistent, but i am seeing it in the range of
> 1-2 seconds.
> Is this by design?

No.

>  I need an simple clocksource which is consistent
> between the host and the guest. Is using HPET in the guest a good idea
> for this, or is that also emulated by KVM ?
>

It is also emulated.

The discrepancy may be due to ntp adjusting the time, and kvmclock not
compensating.  Are you running ntp on your host?  What about the guest?

-- 
error compiling committee.c: too many arguments to function


      reply	other threads:[~2012-03-07 10:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-20  9:14 KVMClock skew Prateek Sharma
2012-03-07 10:46 ` Avi Kivity [this message]

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