Re: [REGRESSION] [PATCH v3 7/7] sched/eevdf: Move to a single runqueue

[Mike Galbraith]

On Thu, 2026-09-24 at 00:48 +0800, Chen Yu wrote:
> 
> Would disabling WA_WEIGHT help? I happened to find that this workaround works
> for me to restore netperf performance (though it is a throughput score rather
> than a latency one), it seems that task_h_load() becomes much
> larger(also on sched/task_h_load):
> echo NO_WA_WEIGHT > /sys/kernel/debug/sched/features
> https://lore.kernel.org/lkml/aoxah90s0bQ4tcUW@three-body/ ;

A long while back, I caught WA_WEIGHT causing firefox's event thread
pool to stack on a single CPU.  In that particular case, the victims
(32 of 'em in 8 rq box!) did nothing but go back to sleep, so no real
harm was done. However, I also measured modest real stacking impact, so
gave task_h_load() a floor on GP.

Perhaps weightless burst stacking is a bigger deal for some than it was
here?  That firefox event thread burst showed potential.
 
	-Mike