On Fri 02-10-20 09:50:02, David Hildenbrand wrote: > >>> - huge page sizes controllable by the userspace? > >> > >> It might be good to allow advanced users to choose the page sizes, so they > >> have better control of their applications. > > > > Could you elaborate more? Those advanced users can use hugetlb, right? > > They get a very good control over page size and pool preallocation etc. > > So they can get what they need - assuming there is enough memory. > > > > I am still not convinced that 1G THP (TGP :) ) are really what we want > to support. I can understand that there are some use cases that might > benefit from it, especially: Well, I would say that internal support for larger huge pages (e.g. 1GB) that can transparently split under memory pressure is a useful funtionality. I cannot really judge how complex that would be consideting that 2MB THP have turned out to be quite a pain but situation has settled over time. Maybe our current code base is prepared for that much better. Exposing that interface to the userspace is a different story of course. I do agree that we likely do not want to be very explicit about that. E.g. an interface for address space defragmentation without any more specifics sounds like a useful feature to me. It will be up to the kernel to decide which huge pages to use. -- Michal Hocko SUSE Labs
