On Tue 20-03-18 21:37:42, Tetsuo Handa wrote: > Michal Hocko wrote: > > On Tue 20-03-18 20:57:56, Tetsuo Handa wrote: > > > I got "oom_reaper: unable to reap pid:" messages when the victim thread > > > was blocked inside free_pgtables() (which occurred after returning from > > > unmap_vmas() and setting MMF_OOM_SKIP). We don't need to complain when > > > __oom_reap_task_mm() returned true (by e.g. finding MMF_OOM_SKIP already > > > set) when oom_reap_task() was trying MAX_OOM_REAP_RETRIES'th attempt. > > > > > > [ 663.593821] Killed process 7558 (a.out) total-vm:4176kB, anon-rss:84kB, file-rss:0kB, shmem-rss:0kB > > > [ 664.684801] oom_reaper: unable to reap pid:7558 (a.out) > > > > I do not see "oom_reaper: reaped process..." so has the task been > > reaped? > > The log is http://I-love.SAKURA.ne.jp/tmp/serial-20180320.txt.xz . xzgrep oom_reaper: serial-20180320.txt.xz [ 97.144805] oom_reaper: reaped process 2142 (cleanupd), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 103.447171] oom_reaper: reaped process 659 (NetworkManager), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 208.906879] oom_reaper: reaped process 1415 (postgres), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 214.179760] oom_reaper: reaped process 588 (irqbalance), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 215.013260] oom_reaper: reaped process 591 (systemd-logind), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 221.483724] oom_reaper: reaped process 7388 (a.out), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 223.140437] oom_reaper: reaped process 9252 (a.out), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 224.735597] oom_reaper: reaped process 9257 (a.out), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 226.608508] oom_reaper: unable to reap pid:9261 (a.out) [ 354.342331] oom_reaper: unable to reap pid:16611 (a.out) [ 380.525910] oom_reaper: unable to reap pid:6927 (a.out) [ 408.397539] oom_reaper: unable to reap pid:6927 (a.out) [ 435.702005] oom_reaper: unable to reap pid:7554 (a.out) [ 466.269660] oom_reaper: unable to reap pid:7560 (a.out) [ 495.621196] oom_reaper: unable to reap pid:7563 (a.out) [ 534.279602] oom_reaper: reaped process 22038 (a.out), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 536.271631] oom_reaper: unable to reap pid:6928 (a.out) [ 600.285293] oom_reaper: unable to reap pid:7550 (a.out) [ 664.684801] oom_reaper: unable to reap pid:7558 (a.out) [ 743.188067] oom_reaper: reaped process 7562 (a.out), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [ 744.980868] oom_reaper: unable to reap pid:6928 (a.out) None of the reaped taks is reported as "unable to reap..." So what actually gets fixed by this patch? -- Michal Hocko SUSE Labs