• Lars R. Damerow's avatar
    mm/memcontrol: export memcg.swap watermark via sysfs for v2 memcg · e0e0b412
    Lars R. Damerow authored
    This patch is similar to commit 8e20d4b3 ("mm/memcontrol: export
    memcg->watermark via sysfs for v2 memcg"), but exports the swap counter's
    watermark.
    
    We allocate jobs to our compute farm using heuristics determined by memory
    and swap usage from previous jobs.  Tracking the peak swap usage for new
    jobs is important for determining when jobs are exceeding their expected
    bounds, or when our baseline metrics are getting outdated.
    
    Our toolset was written to use the "memory.memsw.max_usage_in_bytes" file
    in cgroups v1, and altering it to poll cgroups v2's "memory.swap.current"
    would give less accurate results as well as add complication to the code. 
    Having this watermark exposed in sysfs is much preferred.
    
    Link: https://lkml.kernel.org/r/20230524181734.125696-1-lars@pixar.comSigned-off-by: default avatarLars R. Damerow <lars@pixar.com>
    Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
    Cc: Jonathan Corbet <corbet@lwn.net>
    Cc: Michal Hocko <mhocko@kernel.org>
    Cc: Muchun Song <muchun.song@linux.dev>
    Cc: Roman Gushchin <roman.gushchin@linux.dev>
    Cc: Shakeel Butt <shakeelb@google.com>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Zefan Li <lizefan.x@bytedance.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    e0e0b412
memcontrol.c 203 KB