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

[Vlastimil Babka]

On 2/20/24 18:30, Andrew Morton wrote:
> On Tue, 20 Feb 2024 10:37:03 +0500 Mikhail Gavrilov <mikhail.v.gavrilov@xxxxxxxxx> wrote:
> 
>> On Tue, Feb 20, 2024 at 4:50 AM Vlastimil Babka <vbabka@xxxxxxx> wrote:
>> > >
>> > > I'm all confused.
>> > >
>> > > 4434a56ec209 ("stackdepot: make fast paths lock-less again") was
>> > > mainlined for v6.8-rc3.
>> >
>> > Uh sorry, I just trusted the info that it's not merged and didn't verify
>> > it myself. Yeah, I can see it is there.
>> >
>> 
>> Wait, I am talk about these two patches which is not merged yet:
>> [PATCH v2 1/2] stackdepot: use variable size records for non-evictable entries
>> [PATCH v2 2/2] kasan: revert eviction of stack traces in generic mode
>> https://lore.kernel.org/linux-mm/20240129100708.39460-1-elver@xxxxxxxxxx/
> 
> A can move those into the 6.8-rc hotfixes queue, and it appears a
> cc:stable will not be required.
> 
> However I'm not seeing anything in the changelogs to indicate that
> we're fixing a dramatic performance regression, nor why that
> regressions is occurring.

We also seem have an unhappy bot with the 2/2 patch :/ although it's not yet
clear if it's a genuine issue.

https://lore.kernel.org/all/202402201506.b7e4b9b6-oliver.sang@xxxxxxxxx/