Re: [PATCH] sched/fair: util_est: fast ramp-up EWMA on utilization increases

From: Peter Zijlstra
Date: Thu Oct 17 2019 - 04:25:52 EST

On Mon, Oct 14, 2019 at 05:16:02PM +0100, Douglas Raillard wrote:

> random idea: Since these things are much easier to understand by looking at a graph
> of util over time, we may agree on some mailing-list-friendly way to convey graphs.

I don't think that this patch warrants something like that. It is fairly
clear what it does.

For other stuff, maybe.

> For example, a simple CSV with:
> * before/after delimiters (line of # or =)
> * graph title
> * one point per signal transition, so that it can be plotted with gnuplot style "steps" or matplotlib drawstyle='steps-post'
> * consistent column names:
> - time: in seconds (scientific notation for nanoseconds)
> - activation: 1 when the task is actually running, 0 otherwise
> (so it can be turned into transparent coloured bands like using gnuplot filledcurves, like in [1])
> - util: util_avg of the task being talked about
> The delimiters allow writing a scripts to render graphs directly out of an mbox file or ML archive URL.
> This won't solve the issue for the commit message itself, but that may ease the ML discussions.

Something like that could work; mutt can easily pipe emails into
scripts. OTOH gnuplot also has ASCII output, so one can easily stick
something like that into email.