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* KVMClock skew
@ 2012-02-20  9:14 Prateek Sharma
  2012-03-07 10:46 ` Avi Kivity
  0 siblings, 1 reply; 2+ messages in thread
From: Prateek Sharma @ 2012-02-20  9:14 UTC (permalink / raw)
  To: kvm

   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? 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 ?

Thanks,
Prateek

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: KVMClock skew
  2012-02-20  9:14 KVMClock skew Prateek Sharma
@ 2012-03-07 10:46 ` Avi Kivity
  0 siblings, 0 replies; 2+ messages in thread
From: Avi Kivity @ 2012-03-07 10:46 UTC (permalink / raw)
  To: Prateek Sharma; +Cc: kvm

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


^ permalink raw reply	[flat|nested] 2+ messages in thread

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