Re: [Resend][PATCH] cpufreq: conservative: Decrease frequency faster when the timer deferred

From: Viresh Kumar
Date: Mon Nov 07 2016 - 23:04:55 EST

On 07-11-16, 19:27, Stratos Karafotis wrote:
> Yes, it could be done only when we decrease frequency. But I thought that maybe
> this is against conservative governor principle.
> I initially observed this issue on a Snapdragon 808 using conservative on the
> big cluster (A57). The CPU seemed to remain in high frequencies for
> long time (even 10 seconds) before it returns to min.
> So, most probably the load after the deferred period is completely unrelated to
> the previous one. If we apply this heuristic only when the frequency will be
> decreased (and having in mind that we copy the load value from the previous
> period), IMHO I'm afraid that the conservative will be still more aggressive even
> from ondemand governor.

The deferred period here is actually the time for which the CPU was idle and not
doing anything.

And I am not sure why we should be worrying about increasing the frequency steps
for the period for which the CPU was idle.