On Thu, Mar 30, 2017 at 12:40 PM, Tim Murray <timmur...@google.com> wrote: > The current critical vmpressure event > hasn't been that successful in avoiding oom-killer (on 3.18, at > least)--I've been able to get oom-killer to trigger without a > vmpressure event.
Looked at this some more, and this is almost certainly because vmpressure relies on workqueues. Scheduling delay from CFS workqueues would explain vmpressure latency that results in oom-killer running long before the critical vmpressure notification is received in userspace, even if userspace is running as FIFO. We regularly see 10ms+ latency on workqueues, even when an Android device isn't heavily loaded.