On Tue 14-11-23 22:06:45, Charan Teja Kalla wrote: > Thanks Michal!! > > On 11/14/2023 4:18 PM, Michal Hocko wrote: > >> At least in my particular stress test case it just delayed the OOM as i > >> can see that at the time of OOM kill, there are no free pcp pages. My > >> understanding of the OOM is that it should be the last resort and only > >> after doing the enough reclaim retries. CMIW here. > > Yes it is a last resort but it is a heuristic as well. So the real > > questoin is whether this makes any practical difference outside of > > artificial workloads. I do not see anything particularly worrying to > > drain the pcp cache but it should be noted that this won't be 100% > > either as racing freeing of memory will end up on pcp lists first. > > Okay, I don't have any practical scenario where this helped me in > avoiding the OOM. Will comeback If I ever encounter this issue in > practical scenario. > > Also If you have any comments on [PATCH V2 2/3] mm: page_alloc: correct > high atomic reserve calculations will help me. I do not have a strong opinion on that one to be honest. I am not even sure that reserving a full page block (4MB) on small systems as presented is really a good use of memory. -- Michal Hocko SUSE Labs
