Re: [RFC PATCH 0/7] Optimization to reduce the cost of newidle balance

[Matt Fleming]

On Wed, Jul 17, 2024 at 4:53 AM Chen Yu <yu.c.chen@xxxxxxxxx> wrote:
>
> Thanks for your interest in this patch series. The RFC patch series was sent
> out to seek for directions and to see if this issue is worthy to fix. Since
> you have encountered this issue as well and it seems to be generic issue,
> I'll rebase thie patch series and retest it on top of latest kernel and then
> send out a new version.

Great, thanks!

> > I'm seeing this same symptom of burning cycles in update_sd_lb_stats() on an
> > AMD EPYC 7713 machine (128 CPUs, 8 NUMA nodes). The machine is about 50% idle
> > and upadte_sd_lb_stats() sits as the first entry in perf top with about 3.62%
> > of CPU cycles.
>
> May I know what benchmark(test scenario) you are testing? I'd like to replicate
> this test on my machine as well.

Actually this isn't a benchmark -- this was observed on Cloudflare's
production machines. I'm happy to try out your series and report back.

Thanks,
Matt