On Mon, 2 Aug 2010 21:20:40 -0700 (PDT) David Rientjes <rientjes@xxxxxxxxxx> wrote: > On Tue, 3 Aug 2010, KAMEZAWA Hiroyuki wrote: > > > > Yes, but this is what oom_score_adj is intended to do: an oom_score_adj of > > > 300 means task A should be penalized 30% of available memory. A positive > > > oom_score_adj typically means "all other competing tasks should be allowed > > > 30% more memory, cumulatively, compared to this task." Task A uses ~10% > > > of available memory and task B uses 50% of available memory. That's a 40% > > > difference, which is greater than task A's penalization of 30%, so B is > > > killed. > > > > > > > This will confuse LXC(Linux Container) guys. oom_score is unusable anymore. > > > > From Documentation/filesystems/proc.txt in 2.6.35: > > 3.2 /proc/<pid>/oom_score - Display current oom-killer score > ------------------------------------------------------------- > > This file can be used to check the current score used by the > oom-killer is for any given <pid>. Use it together with > /proc/<pid>/oom_adj to tune which process should be killed in an > out-of-memory situation. > > That is unchanged with the rewrite. /proc/pid/oom_score still exports the > badness() score used by the oom killer to determine which task to kill: > the highest score will be killed amongst candidate tasks. The fact that > the score can be influenced by cpuset, memcg, or mempolicy constraint is > irrelevant, we cannot assume anything about the badness() heuristic's > implementation from the score itself. > In old behavior, oom_score order is synchronous both in the system and container. High-score one will be killed. IOW, oom_score have worked as oom_score. But, after the patch, the user (of LXC at el.) can't trust oom_score. Especially with memcg, it just shows a _broken_ value. And user has to caluculate oom_score by himself as real_oom_score = (oom_score - oom_score_adj) * system_memory/container_memory + oom_score_adj. I'm wrong ? Anyway, I think you should take care of this issue. Maybe this breaks google's oom-killer+cpuset system. Thanks, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>