From: Roman Gushchin Subject: kselftests: memcg: speed up the memory.high test 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 Link: https://lkml.kernel.org/r/20220415000133.3955987-3-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin Reviewed-by: David Vernet Cc: Chris Down Cc: Johannes Weiner Cc: Michal Hocko Cc: Shakeel Butt Cc: Tejun Heo Cc: Zefan Li Signed-off-by: Andrew Morton --- tools/testing/selftests/cgroup/test_memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/tools/testing/selftests/cgroup/test_memcontrol.c~kselftests-memcg-speed-up-the-memoryhigh-test +++ a/tools/testing/selftests/cgroup/test_memcontrol.c @@ -607,7 +607,7 @@ static int test_memcg_high(const char *r if (cg_write(memcg, "memory.high", "30M")) goto cleanup; - if (cg_run(memcg, alloc_anon, (void *)MB(100))) + if (cg_run(memcg, alloc_anon, (void *)MB(31))) goto cleanup; if (!cg_run(memcg, alloc_pagecache_50M_check, NULL)) _