[drbd-mc] LCMC feature request to fix clock skew in Windows guests.

[Rasto Levrinc]

On Fri, Mar 22, 2013 at 10:37 AM, Caspar Smit <c.smit at truebit.nl> wrote:
> Hi Rasto,
>
> Thanks, was this included in 1.5.0?
> Where can I find this setting?

No, it will be included in 1.5.1, it's still in vm-clock branch
https://github.com/rasto/lcmc.git

Rasto

>
> Kind regards,
> Caspar Smit
>
> 2013/3/22 Rasto Levrinc <rasto.levrinc at gmail.com>
>>
>> On Thu, Dec 13, 2012 at 2:37 PM, Caspar Smit <c.smit at truebit.nl> wrote:
>> > Hi Rasto,
>> >
>>
>> > I noticed that in Windows 7 and Windows 2008 based VM's the clock of the
>> > guest falls behind the host's clock.
>> > Under heavy load of the VM this can result in 4 minutes behind during a
>> > 15
>> > minutes period, quite a lot.
>> >
>> > To fix this I found a combination of needed options in Libvirt:
>> >
>> > <clock offset='localtime'>
>> >   <timer name='rtc' tickpolicy='catchup'/>
>> >   <timer name='hpet' present='no'/>
>> > </clock>
>>
>> Hi Caspar,
>>
>> it seams that these settings should be ok for both Windows and Linux.
>> I've made "offset" configurable in the LCMC.
>>
>> <clock offset="utc/localtime">
>>         <timer name="rtc" tickpolicy="catchup" />
>>         <timer name="pit" tickpolicy="delay" />
>>         <timer name="hpet" present="no" />
>> </clock>
>>
>> If there's demand to make these timers configurable I'll gladly add it.
>>
>> Thanks,
>> Rasto
>>
>> >
>> > Default LCMC creates:
>> > <clock offset='utc'/>
>> >
>> > offset=localtime is best to use for Windows guests (according to the
>> > qemu-kvm manpage).
>> >
>> > It would be really nice if these libvirt options were configurable in
>> > LCMC.
>> >
>> > Kind regards,
>> >
>> > Caspar Smit



-- 
Dipl.-Ing. Rastislav Levrinc
rasto.levrinc at gmail.com
Linux Cluster Management Console
http://lcmc.sf.net/