Re: [RFC] Paravirt timer for KVM

Gerd Hoffmann
2007-10-16T08:15:25Z

Hollis Blanchard wrote:
> That's a good point, but does PIT/HPET emulation show up as a hot spot
> in any profiles? I think keeping the hypercall API as small as feasible
> is a desirable design goal.

pit probably doesn't due to being rarely updated. For hpet I'd expect
it showing up much more. Asking for current time is a quite frequent
operation in the linux kernel. I've had X86_CR4_TSD set for a while and
saw *lots* of rdtsc traps then ...

cheers,
Gerd