Re: [PATCH 2/4] sched/fair: Track efficiency of task recent_used_cpu

From: Valentin Schneider
Date: Mon Mar 23 2020 - 09:30:31 EST



On Fri, Mar 20 2020, Mel Gorman wrote:
> SIS Recent Used Hit: A recent CPU was eligible and used. Each hit is
> a domain search avoided.
>
> SIS Recent Used Miss: A recent CPU was eligible but unavailable. Each
> time this is hit, there was a penalty to the fast path before
> a domain search happened.
>
> SIS Recent Success Rate: A percentage of the number of hits versus
> the total attempts to use the recent CPU.
>
> SIS Recent Attempts: The total number of times the recent CPU was examined.
> A high number of Recent Attempts with a low Success Rate implies
> the fast path is being punished severely. This could have been
> presented as a weighting of hits and misses but calculating an
> appropriate weight for misses is problematic.
>

Ditto on the raw vs post-processed detail in the changelog, otherwise:

Reviewed-by: Valentin Schneider <valentin.schneider@xxxxxxx>

> Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>