Re: [PATCH v4 1/2] KVM: LAPIC: Optimize timer latency consider world switch time

[Wanpeng Li]

On Wed, 3 Jul 2019 at 22:13, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> On 03/07/19 02:48, Wanpeng Li wrote:
> > Hi Paolo, how about this patchset? Patch 2/2 is easy to take, do you
> > have more concern about patch 1/2?
>
> I don't know.  It seems somewhat hard to tune and in cyclictest it only
> happens for preemption_timer=N.  Are you using preemption_timer=N
> together with the LAPIC-timer-on-service-CPU patches?

A 25ns conservative value makes no benefit for cyclictest any more
even when preemption_timer=N. Btw, maybe it is the time to merge the
LAPIC-timer-on-service-CPU patches now. :)

Regards,
Wanpeng Li