On Thu 05-09-13 12:17:00, azurIt wrote: > >[...] > >> My script detected another freezed cgroup today, sending stacks. Is > >> there anything interesting? > > > >3 tasks are sleeping and waiting for somebody to take an action to > >resolve memcg OOM. The memcg oom killer is enabled for that group? If > >yes, which task has been selected to be killed? You can find that in oom > >report in dmesg. > > > >I can see a way how this might happen. If the killed task happened to > >allocate a memory while it is exiting then it would get to the oom > >condition again without freeing any memory so nobody waiting on the > >memcg_oom_waitq gets woken. We have a report like that: > >https://lkml.org/lkml/2013/7/31/94 > > > >The issue got silent in the meantime so it is time to wake it up. > >It would be definitely good to see what happened in your case though. > >If any of the bellow tasks was the oom victim then it is very probable > >this is the same issue. > > Here it is: > http://watchdog.sk/lkml/kern5.log $ grep "Killed process \<103[168]\>" kern5.log $ So none of the sleeping tasks has been killed previously. > Processes were killed by my script OK, I am really confused now. The log contains a lot of in-kernel memcg oom killer messages: $ grep "Memory cgroup out of memory:" kern5.log | wc -l 809 This suggests that the oom killer is not disabled. What exactly has you script done? > at about 11:05:35. There is an oom killer striking at 11:05:35: Sep 5 11:05:35 server02 kernel: [1751856.433101] Task in /1066/uid killed as a result of limit of /1066 [...] Sep 5 11:05:35 server02 kernel: [1751856.539356] [ pid ] uid tgid total_vm rss cpu oom_adj oom_score_adj name Sep 5 11:05:35 server02 kernel: [1751856.539745] [ 1046] 1066 1046 228537 95491 3 0 0 apache2 Sep 5 11:05:35 server02 kernel: [1751856.539894] [ 1047] 1066 1047 228604 95488 6 0 0 apache2 Sep 5 11:05:35 server02 kernel: [1751856.540043] [ 1050] 1066 1050 228470 95452 5 0 0 apache2 Sep 5 11:05:35 server02 kernel: [1751856.540191] [ 1051] 1066 1051 228592 95521 6 0 0 apache2 Sep 5 11:05:35 server02 kernel: [1751856.540340] [ 1052] 1066 1052 228594 95546 5 0 0 apache2 Sep 5 11:05:35 server02 kernel: [1751856.540489] [ 1054] 1066 1054 228470 95453 5 0 0 apache2 Sep 5 11:05:35 server02 kernel: [1751856.540646] Memory cgroup out of memory: Kill process 1046 (apache2) score 1000 or sacrifice child And this doesn't list any of the tasks sleeping and waiting for oom resolving so they must have been created after this OOM. Is this the same group? -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>