Re: [PATCH] mm/vmscan: respect cpuset policy during page demotion

Michal Hocko
2022-10-31T08:40:15Z

On Fri 28-10-22 07:22:27, Huang, Ying wrote:
> Michal Hocko <mhocko-IBi9RG/b67k@public.gmane.org> writes:
>
> > On Thu 27-10-22 17:31:35, Huang, Ying wrote:
[...]
> >> I think that it's possible for different processes have different
> >> requirements.
> >>
> >> - Some processes don't care about where the memory is placed, prefer
> >> local, then fall back to remote if no free space.
> >>
> >> - Some processes want to avoid cross-socket traffic, bind to nodes of
> >> local socket.
> >>
> >> - Some processes want to avoid to use slow memory, bind to fast memory
> >> node only.
> >
> > Yes, I do understand that. Do you have any specific examples in mind?
> > [...]
>
> Sorry, I don't have specific examples.

OK, then let's stop any complicated solution right here then. Let's
start simple with a per-mm flag to disable demotion of an address space.
Should there ever be a real demand for a more fine grained solution
let's go further but I do not think we want a half baked solution
without real usecases.

--
Michal Hocko
SUSE Labs