Hi Michal, On Thu 2021-03-18 17:16 +0100, Michal Hocko wrote: > On Mon 15-03-21 16:58:37, Aaron Tomlin wrote: > > In the situation where direct reclaim is required to make progress for > > compaction but no_progress_loops is already over the limit of > > MAX_RECLAIM_RETRIES consider invoking the oom killer. Firstly, thank you for your response. > What is the problem you are trying to fix? If I understand correctly, in the case of a "costly" order allocation request that is permitted to repeatedly retry, it is possible to exceed the maximum reclaim retry threshold as long as "some" progress is being made even at the highest compaction priority. Furthermore, if the allocator has a fatal signal pending, this is not considered. In my opinion, it might be better to just give up straight away or try and use the OOM killer only in the non-costly order allocation scenario to assit reclaim. Looking at __alloc_pages_may_oom() the current logic is to entirely skip the OOM killer for a costly order request, which makes sense. Regards, -- Aaron Tomlin
