On Thu 22-08-24 10:39:09, David Hildenbrand wrote: [...] > But then the question is: does it really make sense to differentiate > difference between an NOFAIL allocation under memory pressure of MAX_ORDER > compared to MAX_ORDER+1 (Linus also touched on that)? It could well take > minutes/hours/days to satisfy a very large NOFAIL allocation. So callers > should be prepared to run into effective lockups ... :/
As pointed out in other subthread. We shouldn't really pretend we support NOFAIL for order > 0, or at least anything > A_SMALL_ORDER and encourage kvmalloc for those users. A nofail order 2 allocation can kill most of the userspace on terribly fragmented system that is kernel allocation heavy. > NOFAIL shouldn't exist, or at least not used to that degree. Let's put whishful thinking aside. Unless somebody manages to go over all existing NOFAIL users and fix them then we should better focus on providing a reasonable clearly documented and enforced semantic. -- Michal Hocko SUSE Labs
