From: David Rientjes Date: Fri, 17 Nov 2017 23:26:27 +0000 (-0800) Subject: mm, compaction: kcompactd should not ignore pageblock skip X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=a0647dc9208fae9124ca38d43a5c3c950d955291;p=linux.git mm, compaction: kcompactd should not ignore pageblock skip Kcompactd is needlessly ignoring pageblock skip information. It is doing MIGRATE_SYNC_LIGHT compaction, which is no more powerful than MIGRATE_SYNC compaction. If compaction recently failed to isolate memory from a set of pageblocks, there is nothing to indicate that kcompactd will be able to do so, or that it is beneficial from attempting to isolate memory. Use the pageblock skip hint to avoid rescanning pageblocks needlessly until that information is reset. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1708151638550.106658@chino.kir.corp.google.com Signed-off-by: David Rientjes Cc: Vlastimil Babka Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/compaction.c b/mm/compaction.c index 85395dc6eb137..ad40d67421f37 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1928,9 +1928,8 @@ static void kcompactd_do_work(pg_data_t *pgdat) .total_free_scanned = 0, .classzone_idx = pgdat->kcompactd_classzone_idx, .mode = MIGRATE_SYNC_LIGHT, - .ignore_skip_hint = true, + .ignore_skip_hint = false, .gfp_mask = GFP_KERNEL, - }; trace_mm_compaction_kcompactd_wake(pgdat->node_id, cc.order, cc.classzone_idx);