| Message ID | 20240308023312.25449-1-wegao@suse.com |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | [v1] memcontrol03: Using clean page cache to avoid dependency on IO rate | expand |
Hi! > Bad IO situation(storage bandwidth ~10MB/sec) will lead background > writeback has uncertain progress for dirty page. So system can not > reclaim enough memory for new process and finally lead a unexpected > OOM. > > memcontrol03.c:218: TPASS: Expect: (A/B/E memory.current=0) ~= 0 > memcontrol03.c:116: TPASS: Child 1918 killed by OOM > memcontrol03.c:224: TPASS: Expect: (A/B memory.current=52588544) ~= 52428800 > memcontrol03.c:129: TFAIL: Expected child 1944 to exit(0), but instead killed by SIGKILL This is strange the order of messages here does not make any sense. the last line in the log shouldn't be there at all, the test should have ended with the "Expect: (A/B memory.current=52588544) ~= 52428800" Can you please send the whole log? > Signed-off-by: Wei Gao <wegao@suse.com> > --- > testcases/kernel/controllers/memcg/memcontrol03.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/testcases/kernel/controllers/memcg/memcontrol03.c b/testcases/kernel/controllers/memcg/memcontrol03.c > index 9c6c808e0..9903ba82b 100644 > --- a/testcases/kernel/controllers/memcg/memcontrol03.c > +++ b/testcases/kernel/controllers/memcg/memcontrol03.c > @@ -201,6 +201,7 @@ static void test_memcg_min(void) > sleep(1); > } > > + sync(); > alloc_anon_in_child(trunk_cg[G], MB(148), 0); > > SAFE_CG_SCANF(trunk_cg[B], "memory.current", "%ld", c); > @@ -217,6 +218,7 @@ static void test_memcg_min(void) > TST_EXP_EXPR(values_close(c[2], 0, 1), > "(A/B/E memory.current=%ld) ~= 0", c[2]); > > + sync(); > alloc_anon_in_child(trunk_cg[G], MB(170), 1); > > SAFE_CG_SCANF(trunk_cg[B], "memory.current", "%ld", c);
Hi! > Bad IO situation(storage bandwidth ~10MB/sec) will lead background > writeback has uncertain progress for dirty page. So system can not > reclaim enough memory for new process and finally lead a unexpected > OOM. > > memcontrol03.c:218: TPASS: Expect: (A/B/E memory.current=0) ~= 0 > memcontrol03.c:116: TPASS: Child 1918 killed by OOM > memcontrol03.c:224: TPASS: Expect: (A/B memory.current=52588544) ~= 52428800 > memcontrol03.c:129: TFAIL: Expected child 1944 to exit(0), but instead killed by SIGKILL So I've read the corresponding bug: https://bugzilla.suse.com/show_bug.cgi?id=1218178 And now I understand what this is supposed to fix. Hover doing sync() is a too big hammer, there is no need to sync the whole system, we just need to make sure that the pages from the file we wrote into are written to a pernament storage, so we likely just need: diff --git a/testcases/kernel/controllers/memcg/memcontrol03.c b/testcases/kernel/controllers/memcg/memcontrol03.c index e927dfd19..6d9c490b5 100644 --- a/testcases/kernel/controllers/memcg/memcontrol03.c +++ b/testcases/kernel/controllers/memcg/memcontrol03.c @@ -144,6 +144,7 @@ static void alloc_pagecache_in_child(const struct tst_cg_group *const cg, tst_res(TINFO, "Child %d in %s: Allocating pagecache: %"PRIdPTR, getpid(), tst_cg_group_name(cg), size); alloc_pagecache(fd, size); + SAFE_FSYNC(fd); TST_CHECKPOINT_WAKE(CHILD_IDLE); TST_CHECKPOINT_WAIT(TEST_DONE);
diff --git a/testcases/kernel/controllers/memcg/memcontrol03.c b/testcases/kernel/controllers/memcg/memcontrol03.c index 9c6c808e0..9903ba82b 100644 --- a/testcases/kernel/controllers/memcg/memcontrol03.c +++ b/testcases/kernel/controllers/memcg/memcontrol03.c @@ -201,6 +201,7 @@ static void test_memcg_min(void) sleep(1); } + sync(); alloc_anon_in_child(trunk_cg[G], MB(148), 0); SAFE_CG_SCANF(trunk_cg[B], "memory.current", "%ld", c); @@ -217,6 +218,7 @@ static void test_memcg_min(void) TST_EXP_EXPR(values_close(c[2], 0, 1), "(A/B/E memory.current=%ld) ~= 0", c[2]); + sync(); alloc_anon_in_child(trunk_cg[G], MB(170), 1); SAFE_CG_SCANF(trunk_cg[B], "memory.current", "%ld", c);
Bad IO situation(storage bandwidth ~10MB/sec) will lead background writeback has uncertain progress for dirty page. So system can not reclaim enough memory for new process and finally lead a unexpected OOM. memcontrol03.c:218: TPASS: Expect: (A/B/E memory.current=0) ~= 0 memcontrol03.c:116: TPASS: Child 1918 killed by OOM memcontrol03.c:224: TPASS: Expect: (A/B memory.current=52588544) ~= 52428800 memcontrol03.c:129: TFAIL: Expected child 1944 to exit(0), but instead killed by SIGKILL Signed-off-by: Wei Gao <wegao@suse.com> --- testcases/kernel/controllers/memcg/memcontrol03.c | 2 ++ 1 file changed, 2 insertions(+)