Re: [PATCH 6/8] cpufreq/schedutil: sum per-sched class utilization

From: Steve Muckle
Date: Wed Mar 16 2016 - 14:20:51 EST


On 03/16/2016 12:38 AM, Peter Zijlstra wrote:
> Somewhere in the giant discussions I mentioned that we should be looking
> at a CPPC like interface and pass {min,max} tuples to the cpufreq
> selection thingy.
>
> In that same discussion I also mentioned that we must compute min as the
> hard dl reservation, but that for max we can actually use the avg dl +
> avg rt + avg cfs.
>
> That way there is far more room for selecting a sensible frequency.

Doesn't the above min/max policy mean that the platform will likely
underserve the task load? If avg dl+rt+cfs represents our best estimate
of the work to be done, I would think that should be the min.