From: gaoxiang17 <gaoxiang17@xxxxxxxxxx> Signed-off-by: gaoxiang17 <gaoxiang17@xxxxxxxxxx> --- mm/page_alloc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0aefae4a26b2..8b0634d1728b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1818,6 +1818,13 @@ static bool can_steal_fallback(unsigned int order, int start_mt) if (order >= pageblock_order) return true; + /* + * movable pages won't cause permanent fragmentation, so when you alloc small pages, + * you just need to temporarily steal unmovable or reclaimable pages that are closest + * to the request size. After a while, memory compact may occur to form large contiguous + * pages, and the next movable allocation may not need to steal. Unmovable and reclaimable + * allocation need to actually steal pages. + */ if (order >= pageblock_order / 2 || start_mt == MIGRATE_RECLAIMABLE || start_mt == MIGRATE_UNMOVABLE || -- 2.34.1
