Re: [PATCH RFC] sched/fair: bump sd->max_newidle_lb_cost when newidle balance fails
From: Vincent Guittot
Date: Fri Jun 27 2025 - 09:32:55 EST
On Thu, 26 Jun 2025 at 16:55, Chris Mason <clm@xxxxxxxx> wrote:
>
> On 6/26/25 10:26 AM, Vincent Guittot wrote:
> > On Thu, 26 Jun 2025 at 12:58, Chris Mason <clm@xxxxxxxx> wrote:
>
> >> Got it, I'll play with that. Vincent, was there a benchmark I can use
> >> to see if I've regressed the case you were focused on?
> >
> > It's not a public benchmark but I had some unitary tests with tasks
> > waiting on a busy CPU while other CPUs become idle for a "long" time
> > (but still less than 500us in average). This is even more true with
> > frequency scaling which will minimize the idle duration by decreasing
> > the frequency
>
> Ok, I don't think I'll be able to reliably recreate that on my own, can
> I ask you to rerun against the v2 I sent out?
Yes, I will run some tests
Vincent
>
> -chris