Most of the memory overhead of a memcg object is due to memcg stats maintained by the kernel. Since stats updates happen in performance critical codepaths, the stats are maintained per-cpu and numa specific stats are maintained per-node * per-cpu. This drastically increase the overhead on large machines i.e. large of CPUs and multiple numa nodes. This patch series tries to reduce the overhead by at least not allocating the memory for stats which are not memcg specific. The main change from the v1 is the indirection approach used in this patchset instead of rearranging the members of node_stat_item. Shakeel Butt (7): memcg: reduce memory size of mem_cgroup_events_index memcg: dynamically allocate lruvec_stats memcg: reduce memory for the lruvec and memcg stats memcg: cleanup __mod_memcg_lruvec_state memcg: pr_warn_once for unexpected events and stats memcg: use proper type for mod_memcg_state mm: cleanup WORKINGSET_NODES in workingset include/linux/memcontrol.h | 75 ++---------- mm/memcontrol.c | 245 ++++++++++++++++++++++++++++++++----- mm/workingset.c | 7 +- 3 files changed, 230 insertions(+), 97 deletions(-) -- 2.43.0
