[ntp:questions] Need suggestion on compensating clock drift on Xen based VPS

Ryan Malayter malayter at gmail.com
Fri Nov 13 15:36:54 UTC 2009

On Thu, Nov 12, 2009 at 7:24 AM, Ulrich Windl
<Ulrich.Windl at rz.uni-regensburg.de> wrote:
> Maybe Dave could write an article about "Time in virtual machines" (if
> not done already) ;-)

I'm not too sure how much that would help anybody. It would probably
go something like this:

1) Timekeeping in VMs sucks, but out of necessity. The timing hardware
is virtualized inside each guest, and each VM only gets "slices" of
real CPU and wall-clock time, so timekeeping is difficult.
2) The process by which the timing hardware is virtualized is
implementation-specific. VMware Server, WMware ESX, Xen, Hyper-V, KVM,
etc. all do this a little differently. Consult your virtualization
software's documentation for best practices regarding timekeeping
inside virutalized guests. Some may have custom drivers or other tools
to help.


More information about the questions mailing list