On Thu 17-12-20 13:52:38, Pavel Tatashin wrote: > + * 1. Pinned pages: (long-term) pinning of movable pages is avoided > + * when pages are pinned and faulted, but it is still possible that > + * address space already has pages in ZONE_MOVABLE at the time when > + * pages are pinned (i.e. user has touches that memory before > + * pinning). In such case we try to migrate them to a different zone, > + * but if migration fails the pages can still end-up pinned in > + * ZONE_MOVABLE. In such case, memory offlining might retry a long > + * time and will only succeed once user application unpins pages.
I still dislike this. Pinning can fail so there shouldn't be any reasons to break MOVABLE constrain for something that can be handled. If anything there should be a very good reasoning behind this decision documented. -- Michal Hocko SUSE Labs
