On Tue, Feb 22, 2022 at 04:32:29PM -0800, srinivas pandruvada wrote:
> Hi Doug,
>
> On Tue, 2022-02-22 at 16:07 -0800, Doug Smythies wrote:
> > Hi All,
> >
> > I am about 1/2 way through testing Feng's "hacky debug patch",
> > let me know if I am wasting my time, and I'll abort. So far, it
> > works fine.
> This just proves that if you add some callback during long idle, you
> will reach a less aggressive p-state. I think you already proved that
> with your results below showing 1W less average power ("Kernel 5.17-rc3
> + Feng patch (6 samples at 300 sec per").
>
> Rafael replied with one possible option. Alternatively when planing to
> enter deep idle, set P-state to min with a callback like we do in
> offline callback.
Yes, if the system is going to idle, it makes sense to goto a lower
cpufreq first (also what my debug patch will essentially lead to).
Given cprfreq-util's normal running frequency is every 10ms, doing
this before entering idle is not a big extra burden.
Thanks,
Feng
> So we need to think about a proper solution for this.
>
> Thanks,
> Srinivas
