Re: [RFC 3/4] sched/fair: replace runnable load average by runnable average

From: Peter Zijlstra
Date: Thu Feb 13 2020 - 12:36:24 EST


On Tue, Feb 11, 2020 at 06:46:50PM +0100, Vincent Guittot wrote:
> @@ -367,6 +367,14 @@ struct util_est {
> * For cfs_rq, it is the aggregated load_avg of all runnable and
> * blocked sched_entities.
> *
> + * [runnable_avg definition]
> + *
> + * runnable_avg = runnable%

* SCHED_CAPACITY_SCALE

right, just like we have for util_avg.

> + *
> + * where runnable% is the time ratio that a sched_entity is runnable.
> + * For cfs_rq, it is the aggregated runnable_avg of all runnable and
> + * blocked sched_entities.

Which is a verbatim repeat of the runnable% definition for load_avg,
right? Perhaps re-arrange the text such that we only have a single
definition for each symbol?

> + *
> * [util_avg definition]
> *
> * util_avg = running% * SCHED_CAPACITY_SCALE

Can you please split this patch in two? First remove everything
runnable_load_avg, and then introduce runnable_avg.

I didn't quickly spot anything off, and you're right that runnable vs
util is an interesting signal.