Re: [patch 0/3] kvm tool: Serial emulation overhaul

From: Avi Kivity
Date: Tue Dec 13 2011 - 09:58:50 EST


On 12/13/2011 04:51 PM, Thomas Gleixner wrote:
> > > The whole APIC timer calibration and the back and forth
> > > conversion is definitely nothing which falls into the category of
> > > smart.
> >
> > APIC timer calibration is silly but it hasn't proven to be a real-world
> > problem.
>
> Well, that depends on the world.

What I mean by that, is that I haven't seen any bug reports in this area
apart from some issue with wiring the PIT/PIC/APIC correctly which were
resolved long ago.

> The issue with that calibration is
> that it can be off and for a certain category of application it
> matters. Definitely not for the usual virt workload stuff. But saving
> cycles for highres/nohz enabled guests would be nice. Maybe I have a
> go when I find a some time.

Just dropping the calibration an replacing it with a pre-calibrated
value should be simple, if there is a workload that could benefit.

--
error compiling committee.c: too many arguments to function

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