From mboxrd@z Thu Jan  1 00:00:00 1970
From: <kvm-user@goodbit.net>
Subject: XP Guest Clock Slow
Date: Fri, 16 Jan 2009 10:14:51 -0600
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Hello,

I just upgraded my hardware to a VT-capable CPU, and am getting up-to-speed
with kvm.

The clock on my XP guest significantly lags (e.g. by 50%) behind the host.
I lose several hours overnight in the guest clock.  (Not just a few seconds)
System load seems to aggravate the problem.

I have seen similar behavior in quick tests on a Vista client.
My Ubuntu client is fine, presumably due to clocksource==kvm-clock in guest.


Everything else works fine in all guest VMs.  (Amazingly well, actually)
Performance is equal to or better what I have been used to with VMware
Server.

Host CPU is Athlon 64 X2 with SB700 chipset.
System dumps (lspci, cpuinfo, etc) available on request (I don't want to
flood)

Host environment is Debian Lenny, with the distribution 2.6.26 kernel.
Currently running a locally compiled/installed kvm-82
I also saw the same issue with the kvm-72 Debian package.

My host clock is set to 'hpet'
| /sys/devices/system/clocksource/clocksource0$ cat *
| hpet acpi_pm jiffies tsc
| hpet

Is there a paravirtual clock driver for M$ clients available?
What is current best practice to work around this problem?

Thanks,

--
Marty