On Wed, 17 Feb 2010, KAMEZAWA Hiroyuki wrote: > And basically. memcg's oom means "the usage over the limits!!" and does > never means "resouce is exhausted!!". > > Then, marking OOM to zones sounds strange. You can cause oom in 64MB memcg > in 64GB system. > ZONE_OOM_LOCKED is taken system-wide because the result of a memcg oom is that a task will get killed and free memory, so VM_FAULT_OOM doesn't require any additional killing if we're oom, it should just retry after the task has exited. If we remove the zone locking for memcg, it is possible that pagefaults will race with setting TIF_MEMDIE and two tasks get killed instead. I guess that's acceptable considering its just as likely that the memcg will reallocate to the same limit again and cause VM_FAULT_OOM to rekill. -- 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>