Re: [percpu] ace7e70901: aim9.sync_disk_rw.ops_per_sec -2.3% regression

[Roman Gushchin]

On Tue, Apr 27, 2021 at 03:34:48PM +0800, kernel test robot wrote:
> 
> 
> Greeting,
> 
> FYI, we noticed a -2.3% regression of aim9.sync_disk_rw.ops_per_sec due to commit:

Wow, that's very surprising, given that there are no pcpu allocations on any hot
paths there.

I tried hard to reproduce it, and I think I see something, however the data is
very noisy. I'm not sure I can confidently attribute the regression to
ace7e70901 ("percpu: use reclaim threshold instead of running for every page")
rather than
f183324133 ("percpu: implement partial chunk depopulation").

Anyway, in my setup the following patch seems to fix the regression.
Is it possible to test it?

Thank you!

Roman

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