Re: [RFC PATCH v3 0/7] DAMON based tiered memory management for CXL memory

SeongJae Park
2024-04-05T19:28:04Z

Hello Honggyu,

On Fri, 5 Apr 2024 15:08:49 +0900 Honggyu Kim <honggyu.kim@sk.com> wrote:

> There was an RFC IDEA "DAMOS-based Tiered-Memory Management" previously
> posted at [1].
>
> It says there is no implementation of the demote/promote DAMOS action
> are made. This RFC is about its implementation for physical address
> space.
>
>
> Changes from RFC v2:
> 1. Rename DAMOS_{PROMOTE,DEMOTE} actions to DAMOS_MIGRATE_{HOT,COLD}.
> 2. Create 'target_nid' to set the migration target node instead of
> depending on node distance based information.
> 3. Instead of having page level access check in this patch series,
> delegate the job to a new DAMOS filter type YOUNG[2].
> 4. Introduce vmstat counters "damon_migrate_{hot,cold}".
> 5. Rebase from v6.7 to v6.8.

Thank you for patiently keeping discussion and making this great version! I
left comments on each patch, but found no special concerns. Per-page access
recheck for MIGRATE_HOT and vmstat change are taking my eyes, though. I doubt
if those really needed. It would be nice if you could answer to the comments.

Once my comments on this version are addressed, I would have no reason to
object at dropping the RFC tag from this patchset.

Nonetheless, I show some warnings and errors from checkpatch.pl. I don't
really care about those for RFC patches, so no problem at all. But if you
agree to my opinion about RFC tag dropping, and therefore if you will send next
version without RFC tag, please make sure you also run checkpatch.pl before
posting.

Thanks,
SJ …