Re: [PATCH kselftest-next 2/2] kselftests: memcg: speed up the memory.high test

[Chris Down <chris@chrisdown.name>]

Roman Gushchin writes:
>After commit 0e4b01df8659 ("mm, memcg: throttle allocators when
>failing reclaim over memory.high") allocating memory over memory.high
>became very time consuming. But it's exactly what the memory.high
>test from cgroup kselftests is doing: it tries to allocate 100M with
>30M memory.high value. It takes forever to complete.
>
>In order to keep it passing (or failing) in a reasonable amount of
>time let's try to allocate only a little over 30M: 31M to be precise.
>
>With this change test_memcontrol finishes in a reasonable amount of
>time:
>  $ time ./test_memcontrol
>  ok 1 test_memcg_subtree_control
>  ok 2 test_memcg_current
>  ok 3 test_memcg_min
>  ok 4 test_memcg_low
>  ok 5 test_memcg_high
>  ok 6 test_memcg_max
>  ok 7 test_memcg_oom_events
>  ok 8 test_memcg_swap_max
>  ok 9 test_memcg_sock
>  ok 10 test_memcg_oom_group_leaf_events
>  ok 11 test_memcg_oom_group_parent_events
>  ok 12 test_memcg_oom_group_score_events
>
>  real	0m2.273s
>  user	0m0.064s
>  sys	0m0.739s
>
>Signed-off-by: Roman Gushchin <guro@fb.com>
>Cc: Chris Down <chris@chrisdown.name>
>Cc: Johannes Weiner <hannes@cmpxchg.org>

Thanks, this makes sense.

Reviewed-by: Chris Down <chris@chrisdown.name>