Changes since v2: * Rebase on mmotm-2016-06-15-16-18 with Mel's node-based reclaim series dropped locally. Note there will be some small conflicts, but nothing substantial that should complicate readding Mel's series later and invalidate testing. * Dropped patch 18 which was the only major conflict with Mel's series, which solves the same thing, and it wasn't that important in this series. * The rebasing however required some major rewrite of patches 2 and 3 due to changes in mmotm, so I dropped the acks. Changes there should also address reviewers' concerns. E.g. ALLOC_NO_WATERMARKS is used in direct reclaim and compaction attempts after patch 3, as Joonsoo suggested. * In patch 12, compaction retries are now only counted after reaching the final priority (suggested by Michal Hocko). Changes since v1 RFC: * Incorporate feedback from Michal, Joonsoo, Tetsuo * Expanded cleanup of watermark checks controlling reclaim/compaction This is mostly a followup to Michal's oom detection rework, which highlighted the need for direct compaction to provide better feedback in reclaim/compaction loop, so that it can reliably recognize when compaction cannot make further progress, and allocation should invoke OOM killer or fail. We've discussed this at LSF/MM [1] where I proposed expanding the async/sync migration mode used in compaction to more general "priorities". This patchset adds one new priority that just overrides all the heuristics and makes compaction fully scan all zones. I don't currently think that we need more fine-grained priorities, but we'll see. Other than that there's some smaller fixes and cleanups, mainly related to the THP-specific hacks. I've tested this with stress-highalloc in GFP_KERNEL order-4 and GFP_HIGHUSER_MOVABLE order-9 scenarios. There's not much report but noise, except reductions in direct reclaim. order-9: Direct pages scanned 238949 41502 Kswapd pages scanned 2069710 2229295 Kswapd pages reclaimed 1981047 2139089 Direct pages reclaimed 236534 41502 order-4: Direct pages scanned 204214 110733 Kswapd pages scanned 2125221 2179180 Kswapd pages reclaimed 2027102 2098257 Direct pages reclaimed 194942 110695 Also Patch 1 describes reductions in page migration failures. [1] https://lwn.net/Articles/684611/ Hugh Dickins (1): mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode Vlastimil Babka (16): mm, page_alloc: set alloc_flags only once in slowpath mm, page_alloc: don't retry initial attempt in slowpath mm, page_alloc: restructure direct compaction handling in slowpath mm, page_alloc: make THP-specific decisions more generic mm, thp: remove __GFP_NORETRY from khugepaged and madvised allocations mm, compaction: introduce direct compaction priority mm, compaction: simplify contended compaction handling mm, compaction: make whole_zone flag ignore cached scanner positions mm, compaction: cleanup unused functions mm, compaction: add the ultimate direct compaction priority mm, compaction: more reliably increase direct compaction priority mm, compaction: use correct watermark when checking allocation success mm, compaction: create compact_gap wrapper mm, compaction: use proper alloc_flags in __compaction_suitable() mm, compaction: require only min watermarks for non-costly orders mm, vmscan: make compaction_ready() more accurate and readable include/linux/compaction.h | 84 ++++++------- include/linux/gfp.h | 14 ++- include/trace/events/compaction.h | 12 +- include/trace/events/mmflags.h | 1 + mm/compaction.c | 186 +++++++++------------------ mm/huge_memory.c | 29 +++-- mm/internal.h | 7 +- mm/khugepaged.c | 2 +- mm/migrate.c | 2 +- mm/page_alloc.c | 258 ++++++++++++++++++-------------------- mm/vmscan.c | 47 ++++--- tools/perf/builtin-kmem.c | 1 + 12 files changed, 281 insertions(+), 362 deletions(-) -- 2.8.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>