[0/4] memcg: reduce memory consumption by memcg stats

Message

Shakeel Butt April 23, 2024, 5:18 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.

Shakeel Butt (4):
  mm: rearrange node_stat_item to put memcg stats at start
  memcg: reduce memory for the lruvec and memcg stats
  memcg: use proper type for mod_memcg_state
  memcg: restrict __mod_memcg_lruvec_state to memcg stats

 include/linux/memcontrol.h | 25 +++++++++++++------------
 include/linux/mmzone.h     | 29 +++++++++++++++++------------
 mm/memcontrol.c            | 12 +++++++-----
 mm/vmstat.c                | 24 ++++++++++++------------
 4 files changed, 49 insertions(+), 41 deletions(-)