Messages in this thread | | | Date | Fri, 6 Jul 2018 14:40:03 +0100 | From | Quentin Perret <> | Subject | Re: [RFC PATCH v4 08/12] sched: Add over-utilization/tipping point indicator |
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On Friday 06 Jul 2018 at 15:24:28 (+0200), Peter Zijlstra wrote: > On Fri, Jul 06, 2018 at 02:20:57PM +0100, Quentin Perret wrote: > > So, what we try to do here is to _not_ set the overutilized flag based > > on the utilization of a new task, because its utilization is 'wrong'. > > That should help avoiding spurious transitions above the overutilized > > threshold. > > That most certainly deserves a comment,
Ok, will do.
> also didn't util_est fix some of that wrong-ness?
When a new task is enqueued, we don't have util_est samples yet, so the task's util_est is equal to its util_avg. So util_est won't help here, unfortunately.
But it does help in the wake-up path to predict what OPP will be selected (see cpu_util_next() in patch 09/12).
Thanks, Quentin
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