This patchset is related to the compaction. patch 1 fixes contrary implementation of the purpose of compaction. patch 2~4 are for optimization. patch 5 is just for clean-up. I tested this patchset with stress-highalloc benchmark on Mel's mmtest and cannot find any regression in terms of success rate. And I find much reduced system time. Below is result of 3 runs. * Before time :: stress-highalloc 3276.26 user 740.52 system 1664.79 elapsed time :: stress-highalloc 3640.71 user 771.32 system 1633.83 elapsed time :: stress-highalloc 3691.64 user 775.44 system 1638.05 elapsed avg system: 1645 s * After time :: stress-highalloc 3225.51 user 732.40 system 1542.76 elapsed time :: stress-highalloc 3524.31 user 749.63 system 1512.88 elapsed time :: stress-highalloc 3610.55 user 757.20 system 1505.70 elapsed avg system: 1519 s That is 7% reduced system time. Thanks. Joonsoo Kim (5): mm/compaction: disallow high-order page for migration target mm/compaction: do not call suitable_migration_target() on every page mm/compaction: change the timing to check to drop the spinlock mm/compaction: check pageblock suitability once per pageblock mm/compaction: clean-up code on success of ballon isolation mm/compaction.c | 75 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 39 insertions(+), 36 deletions(-) -- 1.7.9.5 -- 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>