On 28-Sep-2013 11:30 AM, "Ryan" <ryanphilips19@googlemail.com> wrote:
>
> Thanks, I understood it!
> Now, From the code, i understand that the only if the load goes beyond
> 95% - he scales up the frequency.
>
> Now, If we assume the load to be 50% now and he is running at a X Frequency.
> Now, what if the load increases from 50% to 70% - Will he bump it up?
> Since it does not cross 95% up threshold?

In the earlier code: yes.. it will inc only if we r above 95..
In the latest code we can inc freq any time..

> Coming back to the load calculation - Load is computed periodically,
> But he considers the total wall time or up time right and total idle
> time from the beginning. It is not just during the "sampling period"
> duration.

No.. load is calculated between samples... only

> Thanks for your time.
>
>
> /Ryan
>
>
>
> On Fri, Sep 27, 2013 at 4:02 AM, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> >
> > On 27-Sep-2013 1:55 AM, "Ryan" <ryanphilips19@googlemail.com> wrote:
> >
> >>
> >> Let me understand how the downscaling works in the older sources.
> >>
> >> So, you mean that -
> >>
> >> 1) Upthreshold = 95%
> >>     down dif = 5%
> >>
> >> so, upthreshold - down diff = 90%
> >>
> >> if load is 85% ; cpu downscaling takes place
> >> if load is 75% ; cpu downscaling takes place
> >>  and so on.
> >>
> >> So everytime for sampling rate period - work queue checks and finds
> >> the load and downscaling takes place if less than 90%.
> >>
> >> What i did not understand is how down diff will make the cpu remain in
> >> the same range for a longer period.
> >>
> >> Am i missing something. could you please give a detailed answer as i
> >> struggling to understand this.
> >>
> >> Thanks for your time.
> >
> > Since my first mail, I have been travelling by an overnight bus and sending
> > u mail by my phone. And it is still not that easy to type with a phone.
> >
> > Suppose load is 96, we switch to max freq.. now load toggles between 90 and
> > 100 for some time... i.e. it goes to 90, 91, 92...100... but not below 90..
> >
> > Then we will not decrease and increase the freq again and again.. but keep
> > running at highest freq..