On 2023/6/28 3:22, Andrew Morton wrote:
On Tue, 27 Jun 2023 21:35:42 +0800 Nanyong Sun <sunnanyong@xxxxxxxxxx> wrote:
Since the ksm_merging_pages information already included in
/proc/<pid>/ksm_stat, we can delete /proc/<pid>/ksm_merging_pages to
make the directory more clean, and can save a little bit resources.
Well, this is a non backward compatible change - any userspace
which depends on ksm_merging_pages will break.
Yes, we could remove this but it will be a lengthy process involving
emitting a "please use ksm_stat instead" message for a few
years before removal.
.
This interface was just added last year(Apr 28 2022) in commit 7609385337a4
("ksm: count ksm merging pages for each process"), it does not have
historical baggage.
Additionally, as stated in the commit message, this interface is mainly
used to query the deduplication effect
of the application for the upper application optimization during the
development phase,
so deleting it would have a very small impact.
