Re: [LSF/MM/BPF TOPIC] DAMON Requirements for Access-aware MM of Future

From: Matthew Wilcox
Date: Wed Jan 01 2025 - 23:09:55 EST


On Wed, Jan 01, 2025 at 02:20:39PM -0800, SeongJae Park wrote:
> Hi all,
>
>
> I find a few interesting and promising projects that aim to do efficient access
> pattern-aware memory management of near future, including below (alphabetically
> sorted).
>
> - CXL hotness monitoring unit
> (https://lore.kernel.org/20241121101845.1815660-1-Jonathan.Cameron@xxxxxxxxxx)
> - Memory tiering fainess by per-cgroup control of promotion and demotion
> (https://lore.kernel.org/20241108190152.3587484-1-kaiyang2@xxxxxxxxxx)
> - Promotion of unmapped page cache folios
> (https://lore.kernel.org/20241210213744.2968-1-gourry@xxxxxxxxxx)

I'm not sure how DAMON can help with this one. As I understand DAMON,
it monitors accesses to user addresses. This patchset is trying to solve
the problem for file pages which aren't mapped to userspace at all.
ie only accessed through read() and write().