On Tue, Sep 08, 2009 at 03:41:59PM -0300, Marcelo Tosatti wrote: > On Wed, Sep 02, 2009 at 10:34:57AM -0400, Glauber Costa wrote: > > KVM clock is great to avoid drifting in guest VMs running ontop of kvm. > > However, the current mechanism will not propagate changes in wallclock value > > upwards. This effectively means that in a large pool of VMs that need accurate timing, > > all of them has to run NTP, instead of just the host doing it. > > > > Since the host updates information in the shared memory area upon msr writes, > > this patch introduces a worker that writes to that msr, and calls do_settimeofday > > at fixed intervals, with second resolution. A interval of 0 determines that we > > are not interested in this behaviour. A later patch will make this optional at > > runtime > > > > Signed-off-by: Glauber Costa <glommer@xxxxxxxxxx> > > As mentioned before, ntp already does this (and its not that heavy is > it?). > > For example, if ntp running on the host, it avoids stepping the clock > backwards by slow adjustment, while the periodic frequency adjustment on > the guest bypasses that. Simple question: How do I run ntp in guests without network? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
