Re: [Xen-devel] Time went backwards

[Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>]

On 10 Mar 2006, at 17:33, Rik van Riel wrote:

> > To that end, it would be interesting to see if after the first 
> > do-while
> > loop in timer_interrupt(), you can end up with sched_time >
> > (processed_system_time + delta).
> >
> > If so, we could end up running per-cpu processed_system_time ahead of
> > current system time and so get -ve delta the *next* time we run
> > timer_interrupt().
> In my observations, delta is always positive.  It is cpu_delta
> which goes negative.  I'll go count the cpu specific deltas and
> will check to see if they are larger than the system wide delta.
Yeah, sorry, I was being sloppy in my terminology. I think comparing 
stolen/blocked delta values with cpu_delta would be useful -- see if 
those are bigger than we'd expect and pushing per-cpu processed time 
too far forward.
 -- Keir


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel