Re: [RFC PATCH v3 0/6] KVM: x86: avoid redundant REQ_EVENT

From: Roman Kagan
Date: Tue Dec 20 2016 - 06:47:31 EST


On Mon, Dec 19, 2016 at 03:30:17PM +0100, Paolo Bonzini wrote:
>
>
> On 19/12/2016 14:05, Denis Plotnikov wrote:
> >>
> > This new patch-set does avoid unnecessary interrupt re-injections -
> > checked.
> >
> > The test (MS Windows, sending messages between multiple windows using
> > windows-specific interface),
> > which showed performance growth with "[PATCH v2] KVM: x86: avoid
> > redundant REQ_EVENT" showed pretty much the same performance level with
> > this new patch-set.
> > The test score difference (+2.4% to [PATCH v2]) is within the tolerance
> > range(5%).
> >
> > The test score on mainstream v4.9 kernel CPU Intel i5-2400, guest
> > Windows Server 2012 2VCPU, 2GB:
> >
> > without patch: 31510 (+/- 4%)
> > with patch: 36270 (+/- 5%)
> >
> > difference = (36270-31510)/31510 * 100 = +15% -- looks good!
>
> Awesome! I hope it also qualifies as less ugly. :)

Absolutely. FWIW

Reviewed-by: Roman Kagan <rkagan@xxxxxxxxxxxxx>

Roman.