[LSF/MM/BPF TOPIC] kernel memory accounting

[Roman Gushchin <guro@fb.com>]

I'm currently working on the new cgroup slab controller [1], which
fundamentally changes how the slab memory is tracked: instead of
creating a separate set of kmem_caches for each memory cgroup a
single global set is used for all non-root allocations. Memcg
ownership is then tracked per-object rather than per-page.

The new approach comes with a much better slab utilization and
allows to reduce the slab memory size by up to ~40%.

It's also creates a foundation for tracking other objects which
aren't page-sized: e.g. percpu allocations, which are scattered
over multiple pages.

I'd like to share latest results and discuss all ongoing questions,
concerns and suggestions.

[1] https://lkml.org/lkml/2019/10/17/1065