On Tue, Apr 13, 2021 at 11:36:08AM +0200, Vlastimil Babka wrote: > On 4/12/21 4:08 PM, Mel Gorman wrote: > > On Mon, Apr 12, 2021 at 02:40:18PM +0200, Vlastimil Babka wrote: > >> On 4/12/21 2:08 PM, Mel Gorman wrote: > > > > the pageset structures in place would be much more straight-forward > > assuming the structures were not allocated in the zone that is being > > hot-removed. > > I would expect this is not possible, at least for ZONE_MOVABLE, as the percpu > allocations should be GFP_KERNEL. True. > And it's not realistic to expect offlining to > succeed at all without using ZONE_MOVABLE. > > AFAIK even Oscar's work on using the node to self-contain its own structures is > only applicable to struct pages, not percpu allocations? That I don't know as I didn't check although in general, it would be somewhat unfortunate if per-cpu structures were remote. It wouldn't be critical given that they'll be in cache assuming the per-cpu structures are not straddling cache lines. -- Mel Gorman SUSE Labs