Re: [PATCH 0/5] mm/khugepaged: add collapse hint machanism for khugepaged and use in mglru

[Zi Yan <ziy@nvidia.com>]

On 11 Jun 2026, at 5:23, Karim Manaouil wrote:

> On Tue, Jun 09, 2026 at 03:44:21PM +0100, Lorenzo Stoakes wrote:
>> On Tue, Jun 09, 2026 at 04:17:45AM -0600, Nico Pache wrote:
>>> I had future plans for something similar as part of the thp=auto work;
>>> however that requires significant thought and investigation into how
>>> we can properly gather hints for collapse/split THP candidates. From
>>> my perspective we'd want a more global structure/system outside of
>>> khugepaged, that would directly call khugepaged (and others like
>>> split, etc). It would also tie into the allocator so that at fault
>>> time it could leverage the hints to make better decisions. My fear
>>> with this series is that making a decision now might complicate future
>>> work by adding complexity we may eventually want to remove for a
>>> better solution.
>>
>> I know this is future planning stuff, but I want to point out that we need
>> to see significant rework of the THP code base before accepting any further
>> major changes.
>>
>>>
>>> If you have the chance perhaps you can lead a discussion on your
>>> proposal at the biweekly MM alignment session.
>>>
>>> +David Rientjes as he leads those discussions. We could use that time
>>> to layout a plan for what needs to be done for this work, and for the
>>> work surrounding thp=auto as I beleive they will be interdependent :)
>>
>> We prefer to discuss THP topics in the THP cabal meeting, which both THP
>> maintainers regularly attend :) having separate sessions we might not be aware
>> of isn't really helpful.
>
> Hi Lorenzo,
>
> How to participate in the THP cabal meetings? Is there any public link
> to join? I'm working recently on anti-fragmentation, which is kind of relevant...

Matthew is hosting the meeting. You can ask him to send you an invite.

>
> Thanks
>> And 'THP auto' is a broad topic rather than a new feature. I don't think it
>> should be seen as a topic 'owned' by anybody, but rather something that we
>> as a community should discuss.
>>
>> Series that appear from nowhere trying to implement significant changes
>> along those lines without community disucssion will not be hugely
>> appreciated :)
>>
>> Thanks, Lorenzo
>
> -- 
> ~karim


Best Regards,
Yan, Zi