[REGESSION] systemd-oomd overreacting due to PSI changes for Btrfs #forregzbot

[Thorsten Leemhuis]

On 03.11.22 11:46, Thorsten Leemhuis wrote:
> On 15.09.22 11:41, Christoph Hellwig wrote:
>> btrfs compressed reads try to always read the entire compressed chunk,
>> even if only a subset is requested.  Currently this is covered by the
>> magic PSI accounting underneath submit_bio, but that is about to go
>> away. Instead add manual psi_memstall_{enter,leave} annotations.
>>
>> Note that for readahead this really should be using readahead_expand,
>> but the additionals reads are also done for plain ->read_folio where
>> readahead_expand can't work, so this overall logic is left as-is for
>> now.
> 
> It seems this patch makes systemd-oomd overreact on my day-to-day
> machine and aggressively kill applications. I'm not the only one that
> noticed such a behavior with 6.1 pre-releases:
> https://bugzilla.redhat.com/show_bug.cgi?id=2133829
> https://bugzilla.redhat.com/show_bug.cgi?id=2134971

Great, the kernel's regression tracker reports a regression and forgets
to tell his regression tracking bot about it to ensure it's tracked... :-D

#regzbot ^introduced 4088a47e78f9
#regzbot title mm/btrfs: systemd-oomd overreacting due to PSI changes
for Btrfs
#regzbot ignore-activity

Ciao, Thorsten