Re: [RFT][PATCH v2 0/3] cpuidle: teo: Do not check timers unconditionally every time

From: Anna-Maria Behnsen
Date: Mon Aug 07 2023 - 11:39:35 EST


On Mon, 7 Aug 2023, Anna-Maria Behnsen wrote:

> On Thu, 3 Aug 2023, Rafael J. Wysocki wrote:
>
> > On Thu, Aug 3, 2023 at 11:12 PM Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
> > >
> > > Hi Folks,
> > >
> > > This is the second iteration of:
> > >
> > > https://lore.kernel.org/linux-pm/4511619.LvFx2qVVIh@kreacher/
> > >
> > > with an additional patch.
> > >
> > > There are some small modifications of patch [1/3] and the new
> > > patch causes governor statistics to play a role in deciding whether
> > > or not to stop the scheduler tick.
> > >
> > > Testing would be much appreciated!
> >
> > For convenience, this series is now available in the following git branch:
> >
> > git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git \
> > pm-cpuidle-teo
> >
>
> Gauthams tests and the distribution of idle time durations looks pretty
> good. Also the prevention of calling tick_nohz_get_sleep_length() is very
> nice (21477 calls of tick_nohz_next_event() and the tick was stopped 2670
> times).
>
> Here is the deviation of idle time durations (based on your branch):

Sorry, s/deviation/distribution

> Idle Total 2670 100.00%
> x >= 4ms 2537 95.02%
> 4ms> x >= 2ms 19 0.71%
> 2ms > x >= 1ms 10 0.37%
> 1ms > x >= 500us 7 0.26%
> 500us > x >= 250us 6 0.22%
> 250us > x >=100us 13 0.49%
> 100us > x >= 50us 17 0.64%
> 50us > x >= 25us 25 0.94%
> 25us > x >= 10us 22 0.82%
> 10us > x > 5us 9 0.34%
> 5us > x 5 0.19%
>
>
> Thanks,
>
> Anna-Maria