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. Changelog since v3: Minor changes related to changing macro names and chaning the if conditions orders. Changelog since v2: Using WARN_ONCE() instead of pr_warn_once() and some changes commit log changes. Also included a patch from Roman. Changelog since v1: The main change from the v1 is the indirection approach used in this patchset instead of rearranging the members of node_stat_item. Roman Gushchin (1): mm: memcg: account memory used for memcg vmstats and lruvec stats 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 mm: cleanup WORKINGSET_NODES in workingset memcg: warn for unexpected events and stats memcg: use proper type for mod_memcg_state include/linux/memcontrol.h | 75 ++---------- mm/memcontrol.c | 244 +++++++++++++++++++++++++++++++------ mm/workingset.c | 7 +- 3 files changed, 222 insertions(+), 104 deletions(-) -- 2.43.0
