[v2,0/7] memcg: reduce memory consumption by memcg stats

Message

Shakeel Butt April 27, 2024, 12:37 a.m. UTC

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(-)