On Fri 10-02-17 09:13:58, Yisheng Xie wrote: > hi Michal, > Thanks for your comment. > > On 2017/2/9 21:41, Michal Hocko wrote: > > On Thu 09-02-17 14:26:28, Michal Hocko wrote: > >> On Thu 09-02-17 20:54:49, Yisheng Xie wrote: > >>> Hi all, > >>> I get an oom on a linux 3.10 kvm guest OS. when it triggers the oom > >>> it have about 24G free memory(and host OS have about 10G free memory) > >>> and watermark is sure ok. > >>> > >>> I also check about about memcg limit value, also cannot find the > >>> root cause. > >>> > >>> Is there anybody ever meet similar problem and have any idea about it? > >>> > >>> Any comment is more than welcome! > >>> > >>> Thanks > >>> Yisheng Xie > >>> > >>> ------------- > >>> [ 81.234289] DefSch0200 invoked oom-killer: gfp_mask=0xd0, order=0, > >>> oom_score_adj=0 > >>> [ 81.234295] DefSch0200 cpuset=/ mems_allowed=0 > >>> [ 81.234299] CPU: 3 PID: 8284 Comm: DefSch0200 Tainted: G O E > >>> ----V------- 3.10.0-229.42.1.105.x86_64 #1 > >>> [ 81.234301] Hardware name: OpenStack Foundation OpenStack Nova, BIOS > >>> rel-1.8.1-0-g4adadbd-20161111_105425-HGH1000008200 04/01/2014 > >>> [ 81.234303] ffff880ae2900000 000000002b3489d7 ffff880b6cec7c58 > >>> ffffffff81608d3d > >>> [ 81.234307] ffff880b6cec7ce8 ffffffff81603d1c 0000000000000000 > >>> ffff880b6cd09000 > >>> [ 81.234311] ffff880b6cec7cd8 000000002b3489d7 ffff880b6cec7ce0 > >>> ffffffff811bdd77 > >>> [ 81.234314] Call Trace: > >>> [ 81.234323] [<ffffffff81608d3d>] dump_stack+0x19/0x1b > >>> [ 81.234327] [<ffffffff81603d1c>] dump_header+0x8e/0x214 > >>> [ 81.234333] [<ffffffff811bdd77>] ? mem_cgroup_iter+0x177/0x2b0 > >>> [ 81.234339] [<ffffffff8115d83e>] check_panic_on_oom+0x2e/0x60 > >>> [ 81.234342] [<ffffffff811c17bf>] > >>> mem_cgroup_oom_synchronize+0x34f/0x580 > >> > >> OK, so this is a memcg OOM killer which panics because the configuration > >> says so. The OOM report doesn't say so and that is the bug. dump_header > >> is memcg aware and mem_cgroup_out_of_memory initializes oom_control > >> properly. Is this Vanilla kernel? > > That means we should raise the limit of that memcg to avoid memcg OOM killer, > right?
Why do you configure the system to panic on memcg OOM in the first place. This is a wrong thing to do in 99% of cases. -- Michal Hocko SUSE Labs
