Re: [PATCH] KVM: LAPIC: Periodically revaluate appropriate lapic_timer_advance_ns

[Wanpeng Li]

On Fri, 9 Aug 2019 at 18:24, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> On 09/08/19 07:45, Wanpeng Li wrote:
> > From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> >
> > Even if for realtime CPUs, cache line bounces, frequency scaling, presence
> > of higher-priority RT tasks, etc can cause different response. These
> > interferences should be considered and periodically revaluate whether
> > or not the lapic_timer_advance_ns value is the best, do nothing if it is,
> > otherwise recaluate again.
>
> How much fluctuation do you observe between different runs?

Sometimes can ~1000 cycles after converting to guest tsc freq.

Regards,
Wanpeng Li