Re: Seeking a KVM benchmark

Gleb Natapov
2014-11-12T15:32:34Z

On Wed, Nov 12, 2014 at 04:26:29PM +0100, Paolo Bonzini wrote:
>
>
> On 12/11/2014 16:22, Gleb Natapov wrote:
> >> > Nehalem results:
> >> >
> >> > userspace exit, urn 17560 17726 17628 17572 17417
> >> > lightweight exit, urn 3316 3342 3342 3319 3328
> >> > userspace exit, LOAD_EFER, guest!=host 12200 11772 12130 12164 12327
> >> > lightweight exit, LOAD_EFER, guest!=host 3214 3220 3238 3218 3337
> >> > userspace exit, LOAD_EFER, guest=host 11983 11780 11920 11919 12040
> >> > lightweight exit, LOAD_EFER, guest=host 3178 3193 3193 3187 3220
> >> >
> > Is this with Andy's patch that skips LOAD_EFER when guest=host, or the one
> > that always switch LOAD_EFER?
>
> Skip LOAD_EFER when guest=host.
>
So guest=host is a little bit better than guest!=host so looks like skipping LOAD_EFER helps, but
why "lightweight exit, urn" worse than guest=host though, it should be exactly the same as long as NX
bit is the same in urn test, no?

--
Gleb.