Re: Stolen and degraded time and schedulers

[Dan Hecht]

> > > How is cpustat->steal used?  How does it get out to usermode?
> > Via /proc/stat, used by modern 'top', maybe other utilities.  It is
> > useful to users who want to see where the time is really going from
> > inside a guest when running on a (para)virtual machine.
> >
> > I believe previous set of xen paravirt-ops patches already handled
> > cases #2 and #3 (but no longer do since switching to clockevents), and
> > the old vmitime code did also.  Obviously, we need revamp this stuff
> > to make it fit in with the new clockevents/hrtimer way of doing things.
>
> I added stolen time accounting to xen-pv_ops last night.  For Xen, at
> least, it wasn't hard to fit into the clockevent infrastructure.  I just
> update the stolen time accounting for each cpu when it gets a timer
> tick; they seem to get a tick every couple of seconds even when idle.

Sounds good.  I don't see this in your patchset you sent yesterday 
though; did you add it after sending out those patches?  if so, could 
you forward the new patch?  does it explicitly prevent stolen time from 
getting accounted as  user/system time or does it just rely on NO_HZ 
mode sort of happening to work that way (since the one shot timer is 
skipped ahead for missed ticks)?

thanks,
Dan
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/