On Wed, 20 Nov 2013, Luigi Semenzato wrote: > Chrome OS uses a custom low-memory notification to minimize OOM kills. > When the notifier triggers, the Chrome browser tries to free memory, > including by shutting down processes, before the full OOM occurs. But > OOM kills cannot always be avoided, depending on the speed of > allocation and how much CPU the freeing tasks are able to use > (certainly they could be given higher priority, but it get complex). > > We may end up using memcg so we can use the cgroup > memory.pressure_level file instead of our own notifier, but we have no > need for finer control over OOM kills beyond the very useful kill > priority. One process at a time is good enough for us. > Even with your own custom low-memory notifier or memory.pressure_level, it's still possible that all memory is depleted and you run into an oom kill before your userspace had a chance to wakeup and prevent it. I think what you'll want is either your custom notifier of memory.pressure_level to do pre-oom freeing but fallback to a userspace oom handler that prevents kernel oom kills until it ensures userspace did everything it could to free unneeded memory, do any necessary logging, etc, and do so over a grace period of memory.oom_delay_millisecs before the kernel eventually steps in and kills. -- 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>