On 1/27/2025 12:31 PM, David Rientjes wrote:
On Fri, 24 Jan 2025, Raghavendra K T wrote:
[...]
By the way, do you have any reason why you'd prefer opt-in prctl
over per-memcg control?
opt-in prctl came in the MM alignment discussion, and have added that.
Are you planning on sending a refresh of that patch series? :)
Hello David,
Current plan is to send by next week.
(Because after measuring the per mm latency and overall latency to do
full scan, I was thinking to add parallel scanning in next version itself).
per-memcg also definitely makes sense. I am not aware which is the most
used usecase. But adding provision for both with one having more
priority over other may be the way to go.
I would suggest leveraging prctl() for this as opposed to memcg. I think
making this part of memcg is beyond the scope for what memcg is intended
to do, limitation of memory resources, similar to the recent discussions
on per-cgroup control for THP.
Additionally, the current memcg configuration of the system may also not
be convenient for using for this purpose, especially if one process should
be opted out in the memcg hierarchy. Requiring users to change how their
memcg is configured just to opt out would be rather unfortunate.
Overall point here is to save time in unnecessary scanning.
will be adding prctl in the upcoming version to start with.
Fully agreed.
Thanks very much for proposing this topic, Raghu, I think it will be very
useful to discuss! Looking forward to it!
Thank you.
- Raghu
