Re: 6.10/regression/bisected - after f1d97e769152 I spotted increased execution time of the kswapd0 process and symptoms as if there is not enough memory

[Filipe Manana]

On Sun, Jul 7, 2024 at 12:35 PM Mikhail Gavrilov
<mikhail.v.gavrilov@xxxxxxxxx> wrote:
>
> On Sat, Jul 6, 2024 at 10:38 PM Filipe Manana <fdmanana@xxxxxxxxxx> wrote:
> > So I've been working on a proper approach following all those test
> > results from you and Mikhail, and I would like to ask you both to try
> > this branch:
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux.git/log/?h=test3_em_shrinker_6.10
> >
> > Again, this is based on 6.10-rc6 plus 3 fixes for this issue you're both having.
> >
> > Can you guys test that branch?
> >
> > Thank you a lot for all the time spent on this!
>
> 6.10.0-rc6-test1_em_shrinker_6.10
> up  1:01
> root         269 25.8  0.0      0     0 ?        R    10:59  15:47 [kswapd0]
> up  2:00
> root         269 25.5  0.0      0     0 ?        S    10:59  30:46 [kswapd0]
> up  3:00
> root         269 27.9  0.0      0     0 ?        S    10:59  50:18 [kswapd0]
> up  4:00
> root         269 27.8  0.0      0     0 ?        S    10:59  67:08 [kswapd0]
> up  5:00
> root         269 27.5  0.0      0     0 ?        S    10:59  83:01 [kswapd0]
> up  6:00
> root         269 27.5  0.0      0     0 ?        S    10:59  99:31 [kswapd0]
> kswapd0 on the test1 branch is bad as
> https://gist.githubusercontent.com/fdmanana/9cea16ca56594f8c7e20b67dc66c6c94/raw/557bd5f6b37b65d210218f8da8987b74bfe5e515/gistfile1.txt
>
>
> 6.10.0-rc6-test2_em_shrinker_6.10
> up  1:00
> root         269 11.7  0.0      0     0 ?        S    19:23   7:03 [kswapd0]
> up  2:02
> root         269 11.9  0.0      0     0 ?        S    19:23  14:38 [kswapd0]
> up  3:00
> root         269 11.9  0.0      0     0 ?        S    19:23  21:30 [kswapd0]
> up  4:01
> root         269 11.2  0.0      0     0 ?        S    19:23  27:15 [kswapd0]
> up  5:00
> root         269 11.4  0.0      0     0 ?        R    Jul06  34:25 [kswapd0]
> up  6:00
> root         269 13.9  0.0      0     0 ?        S    Jul06  50:14 [kswapd0]
> On the test2 branch, kswapd0 is two times better.
>
>
> 6.10.0-rc6-test3_em_shrinker_6.10 (d22fedf5058d)
> up  1:02
> root         269 11.0  0.0      0     0 ?        S    09:54   6:50 [kswapd0]
> up  2:00
> root         269 10.7  0.0      0     0 ?        S    09:54  12:54 [kswapd0]
> up  3:00
> root         269 10.1  0.0      0     0 ?        S    09:54  18:18 [kswapd0]
> up  4:00
> root         269  9.5  0.0      0     0 ?        S    09:54  23:03 [kswapd0]
> up  5:01
> root         269 10.0  0.0      0     0 ?        S    09:54  30:24 [kswapd0]
> up  6:00
> root         269  9.9  0.0      0     0 ?        S    09:54  35:42 [kswapd0]
> On the test3 branch, kswapd0 is thee times better.

That's good. And is the DE unresponsiveness gone too?

I see you tested d22fedf5058d, but I updated the branch a couple hours
ago, now the top commit is fa8b5dd7fa18.
Can you test the updated branch? It may help further in your case.

https://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux.git/commit/?h=test3_em_shrinker_6.10&id=fa8b5dd7fa18a4dc2ea6bdeaf5525b1af348f383

>
> To catch up with the 6.9 branch, the timing needs to be 4 times better.

Hopefully it will be much closer to that with the updated branch.
The upcoming changes for 6.11 would help there too, but anyway we can
still further optimize on top of the 6.10-rc code.

Thanks Mikhail!

>
> --
> Best Regards,
> Mike Gavrilov.