Re: [PATCH v2 1/3] sched/fair: fix rounding issue for asym packing

From: Vincent Guittot
Date: Wed Dec 19 2018 - 10:20:41 EST


On Wed, 19 Dec 2018 at 16:11, Valentin Schneider
<valentin.schneider@xxxxxxx> wrote:
>
> On 19/12/2018 15:05, Vincent Guittot wrote:
> [...]
> >> True, I had a look at the trace and there doesn't seem to be any running
> >> task on that CPU. That's a separate matter however - the rounding issues
> >> can happen regardless of the wl values.
> >
> > But it means that the rounding fix +1 works and your problems comes
> > from something else
>
> Oh yes, I never said it didn't work - I was doing some investigation on
> the reason as to why we'd need this fix, because it's wasn't explicit from
> the commit message.
>
> The rounding errors are countered by the +1, yes, but I'd rather remove
> the errors altogether and go for the snippet I suggested in my previous
> reply.

except that you don't always want to migrate all group load.
I prefer keeping current algorithm and fix it for now. Trying "new"
thing can come in a 2nd step