Re: [GIT PULL] Scheduler changes for v6.8

[Vincent Guittot]

On Mon, 15 Jan 2024 at 13:09, Qais Yousef <qyousef@xxxxxxxxxxx> wrote:
>
> On 01/15/24 09:21, Vincent Guittot wrote:
>
> > > Or I've done the math wrong :-) But the two don't behave the same for the same
> > > kernel with and without CPPC.
> >
> > They will never behave the same because they can't
> > - with invariance, the utilization is the utilization at max capacity
> > so we can easily jump several OPP to go directly to the right one
> > - without invariance, the utilization is the utilization at current
> > OPP so we can only jump to a limited number of OPP
>
> I am probably missing some subtlty, but the  behavior looks more sensible to
> me when we divide by current capacity instead of max one.
>
> It seems what you're saying is that the capacity range for each OPP is 0-1024.

Yes that's the case when you don't have frequency invariance

> And that's when we know that we saturated the current capacity level we decide
> to move on.

yes

>
> As I am trying to remove the hardcoded headroom values I am wary of another
> one. But it seems this is bandaid scenario anyway; so maybe I shouldn't worry
> too much about it.
>
>
> Cheers
>
> --
> Qais Yousef