memcg, oom: provide more precise dump info while memcg oom happening
Currently when a memcg oom is happening the oom dump messages is still
global state and provides few useful info for users. This patch prints
more pointed memcg page statistics for memcg-oom and take hierarchy into
consideration:
Based on Michal's advice, we take hierarchy into consideration: supppose
we trigger an OOM on A's limit
root_memcg
|
A (use_hierachy=1)
/ \
B C
|
D
then the printed info will be:
Memory cgroup stats for /A:...
Memory cgroup stats for /A/B:...
Memory cgroup stats for /A/C:...
Memory cgroup stats for /A/B/D:...
Following are samples of oom output:
(1) Before change:
mal-80 invoked oom-killer:gfp_mask=0xd0, order=0, oom_score_adj=0
mal-80 cpuset=/ mems_allowed=0
Pid: 2976, comm: mal-80 Not tainted 3.7.0+ #10
Call Trace:
[<ffffffff8167fbfb>] dump_header+0x83/0x1ca
..... (call trace)
[<ffffffff8168a818>] page_fault+0x28/0x30
<<<<<<<<<<<<<<<<<<<<< memcg specific information
Task in /A/B/D killed as a result of limit of /A
memory: usage 101376kB, limit 101376kB, failcnt 57
memory+swap: usage 101376kB, limit 101376kB, failcnt 0
kmem: usage 0kB, limit 9007199254740991kB, failcnt 0
<<<<<<<<<<<<<<<<<<<<< print per cpu pageset stat
Mem-Info:
Node 0 DMA per-cpu:
CPU 0: hi: 0, btch: 1 usd: 0
......
CPU 3: hi: 0, btch: 1 usd: 0
Node 0 DMA32 per-cpu:
CPU 0: hi: 186, btch: 31 usd: 173
......
CPU 3: hi: 186, btch: 31 usd: 130
<<<<<<<<<<<<<<<<<<<<< print global page state
active_anon:92963 inactive_anon:40777 isolated_anon:0
active_file:33027 inactive_file:51718 isolated_file:0
unevictable:0 dirty:3 writeback:0 unstable:0
free:729995 slab_reclaimable:6897 slab_unreclaimable:6263
mapped:20278 shmem:35971 pagetables:5885 bounce:0
free_cma:0
<<<<<<<<<<<<<<<<<<<<< print per zone page state
Node 0 DMA free:15836kB ... all_unreclaimable? no
lowmem_reserve[]: 0 3175 3899 3899
Node 0 DMA32 free:2888564kB ... all_unrelaimable? no
lowmem_reserve[]: 0 0 724 724
lowmem_reserve[]: 0 0 0 0
Node 0 DMA: 1*4kB (U) ... 3*4096kB (M) = 15836kB
Node 0 DMA32: 41*4kB (UM) ... 702*4096kB (MR) = 2888316kB
120710 total pagecache pages
0 pages in swap cache
<<<<<<<<<<<<<<<<<<<<< print global swap cache stat
Swap cache stats: add 0, delete 0, find 0/0
Free swap = 499708kB
Total swap = 499708kB
1040368 pages RAM
58678 pages reserved
169065 pages shared
173632 pages non-shared
[ pid ] uid tgid total_vm rss nr_ptes swapents oom_score_adj name
[ 2693] 0 2693 6005 1324 17 0 0 god
[ 2754] 0 2754 6003 1320 16 0 0 god
[ 2811] 0 2811 5992 1304 18 0 0 god
[ 2874] 0 2874 6005 1323 18 0 0 god
[ 2935] 0 2935 8720 7742 21 0 0 mal-30
[ 2976] 0 2976 21520 17577 42 0 0 mal-80
Memory cgroup out of memory: Kill process 2976 (mal-80) score 665 or sacrifice child
Killed process 2976 (mal-80) total-vm:86080kB, anon-rss:69964kB, file-rss:344kB
We can see that messages dumped by show_free_areas() are longsome and can
provide so limited info for memcg that just happen oom.
(2) After change
mal-80 invoked oom-killer: gfp_mask=0xd0, order=0, oom_score_adj=0
mal-80 cpuset=/ mems_allowed=0
Pid: 2704, comm: mal-80 Not tainted 3.7.0+ #10
Call Trace:
[<ffffffff8167fd0b>] dump_header+0x83/0x1d1
.......(call trace)
[<ffffffff8168a918>] page_fault+0x28/0x30
Task in /A/B/D killed as a result of limit of /A
<<<<<<<<<<<<<<<<<<<<< memcg specific information
memory: usage 102400kB, limit 102400kB, failcnt 140
memory+swap: usage 102400kB, limit 102400kB, failcnt 0
kmem: usage 0kB, limit 9007199254740991kB, failcnt 0
Memory cgroup stats for /A: cache:32KB rss:30984KB mapped_file:0KB swap:0KB inactive_anon:6912KB active_anon:24072KB inactive_file:32KB active_file:0KB unevictable:0KB
Memory cgroup stats for /A/B: cache:0KB rss:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
Memory cgroup stats for /A/C: cache:0KB rss:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
Memory cgroup stats for /A/B/D: cache:32KB rss:71352KB mapped_file:0KB swap:0KB inactive_anon:6656KB active_anon:64696KB inactive_file:16KB active_file:16KB unevictable:0KB
[ pid ] uid tgid total_vm rss nr_ptes swapents oom_score_adj name
[ 2260] 0 2260 6006 1325 18 0 0 god
[ 2383] 0 2383 6003 1319 17 0 0 god
[ 2503] 0 2503 6004 1321 18 0 0 god
[ 2622] 0 2622 6004 1321 16 0 0 god
[ 2695] 0 2695 8720 7741 22 0 0 mal-30
[ 2704] 0 2704 21520 17839 43 0 0 mal-80
Memory cgroup out of memory: Kill process 2704 (mal-80) score 669 or sacrifice child
Killed process 2704 (mal-80) total-vm:86080kB, anon-rss:71016kB, file-rss:340kB
This version provides more pointed info for memcg in "Memory cgroup stats
for XXX" section.
Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 files changed