Re: regression/bisected commit 773688a6cb24b0b3c2ba40354d883348a2befa38 make my system completely unusable under high load

[Andrey Konovalov]

On Mon, Jan 29, 2024 at 11:25 PM Mikhail Gavrilov
<mikhail.v.gavrilov@xxxxxxxxx> wrote:
>
> On Fri, Jan 19, 2024 at 10:54 PM Mikhail Gavrilov
> <mikhail.v.gavrilov@xxxxxxxxx> wrote:
> >
> I continued to search regressions in 6.8 kernel.
> And found another one.
>
> cc478e0b6bdffd20561e1a07941a65f6c8962cab is the first bad commit
> commit cc478e0b6bdffd20561e1a07941a65f6c8962cab
> Author: Andrey Konovalov <andreyknvl@xxxxxxxxx>
> Date:   Tue Jan 9 23:12:34 2024 +0100
>
>     kasan: avoid resetting aux_lock
>
> Here I spotted a dropped FPS in the game "Shadow of the Tomb Raider".
> For measuring performance I used an internal benchmark.
> Before commit cc478e0b6bdffd20561e1a07941a65f6c8962cab was 111FPS on
> commit aaa2c9a97c22af5bf011f6dd8e0538219b45af88 [1].
> On commit cc478e0b6bdffd20561e1a07941a65f6c8962cab I has only 63FPS [2]
> And unfortunately the stackdepot patchset which I applied on top of
> 6.8-rc2 didn't restore initial performance [3].
>
> [1] https://i.postimg.cc/tgvwPTkz/c11-aaa2c9a97c22af5bf011f6dd8e0538219b45af88.png
> [2] https://i.postimg.cc/pX8vHDCM/c10-cc478e0b6bdffd20561e1a07941a65f6c8962cab.png
> [3] https://i.postimg.cc/hvWCb7dV/6-8-0-0-rc2-with-stackdepot.png

Hi Mikhail,

Please try to apply these two patches on top:
https://lore.kernel.org/linux-mm/20240129100708.39460-1-elver@xxxxxxxxxx/

They effectively revert the change you mentioned.

Thank you for testing!