On Wed 26-02-25 18:00:26, Baoquan He wrote:
> On 02/26/25 at 07:54am, Michal Hocko wrote:
[...]
> > In any case 96a5c186efff seems incorrect because it assumes that the
> > protection has anything to do with how higher zone is populated while
> > the protection fundamentaly protects lower zone from higher zones
> > allocation. Those allocations are independent on the actual memory in
> > that zone.
>
> The protection value was introduced in non-NUMA time, and later adapted
> to NUMA system. While it still only reflects each zone with other zones
> within one specific node. We may need take this opportunity to
> reconsider it, e.g in the FALLBACK zonelists case it needs take crossing
> nodes into account.
Are you suggesting zone fallback list to interleave nodes? I.e.
numa_zonelist_order we used to have in the past and that has been
removed by c9bff3eebc09 ("mm, page_alloc: rip out ZONELIST_ORDER_ZONE").
--
Michal Hocko
SUSE Labs
