On Thu 05-09-13 11:14:30, 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. > pid: 1031 [...] > stack: > [<ffffffff8110f255>] mem_cgroup_oom_synchronize+0x165/0x190 > [<ffffffff810d269e>] pagefault_out_of_memory+0xe/0x120 > [<ffffffff81026f5e>] mm_fault_error+0x9e/0x150 > [<ffffffff81027414>] do_page_fault+0x404/0x490 > [<ffffffff815cb7bf>] page_fault+0x1f/0x30 > [<ffffffffffffffff>] 0xffffffffffffffff [...] > pid: 1036 > stack: > [<ffffffff8110f255>] mem_cgroup_oom_synchronize+0x165/0x190 > [<ffffffff810d269e>] pagefault_out_of_memory+0xe/0x120 > [<ffffffff81026f5e>] mm_fault_error+0x9e/0x150 > [<ffffffff81027414>] do_page_fault+0x404/0x490 > [<ffffffff815cb7bf>] page_fault+0x1f/0x30 > [<ffffffffffffffff>] 0xffffffffffffffff > > pid: 1038 > stack: > [<ffffffff8110f255>] mem_cgroup_oom_synchronize+0x165/0x190 > [<ffffffff810d269e>] pagefault_out_of_memory+0xe/0x120 > [<ffffffff81026f5e>] mm_fault_error+0x9e/0x150 > [<ffffffff81027414>] do_page_fault+0x404/0x490 > [<ffffffff815cb7bf>] page_fault+0x1f/0x30 > [<ffffffffffffffff>] 0xffffffffffffffff -- 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>