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

From: Chris Down
Date: Tue Dec 03 2019 - 11:58:50 EST


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@xxxxxx>
Cc: Chris Down <chris@xxxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>

Thanks, this makes sense.

Reviewed-by: Chris Down <chris@xxxxxxxxxxxxxx>