The global kswapd scans per-zone LRU and reclaims pages regardless of the cgroup. It breaks memory isolation since one cgroup can end up reclaiming pages from another cgroup. Instead we should rely on memcg-aware target reclaim including per-memcg kswapd and soft_limit hierarchical reclaim under memory pressure. In the global background reclaim, we do soft reclaim before scanning the per-zone LRU. However, the return value is ignored. This patch adds the logic where no per-zone reclaim happens if the soft reclaim raise the free pages above the zone's high_wmark. This is part of the effort which tries to reduce reclaiming pages in global LRU in memcg. The per-memcg background reclaim patchset further enhances the per-cgroup targetting reclaim, which I should have V4 posted shortly. Try running multiple memory intensive workloads within seperate memcgs. Watch the counters for both soft_steal in memory.stat and skip_reclaim in zoneinfo. $ egrep 'steal|scan' /dev/cgroup/A/memory.stat soft_steal 304640 total_soft_steal 304640 $ egrep skip /proc/zoneinfo nr_skip_reclaim_global 0 nr_skip_reclaim_global 381 nr_skip_reclaim_global 387 Ying Han (2): check the return value of soft_limit reclaim add two stats to monitor soft_limit reclaim. Documentation/cgroups/memory.txt | 2 ++ include/linux/memcontrol.h | 5 +++++ include/linux/mmzone.h | 1 + mm/memcontrol.c | 14 ++++++++++++++ mm/vmscan.c | 16 +++++++++++++++- mm/vmstat.c | 1 + 6 files changed, 38 insertions(+), 1 deletions(-) -- 1.7.3.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>