On Fri, Dec 06, 2024 at 10:33:56PM +0000, Matthew Wilcox wrote: > On Fri, Dec 06, 2024 at 02:27:36PM -0800, Shakeel Butt wrote: > > For anon memory or specifically THPs allocation, we can tune though > > sysctls to be less aggressive but there is infrastructure like > > khugepaged which in background converts small pages into THPs. I can > > imagine that we might want something similar for filesystem as well. > > khugepaged also works on files. Where Somebody Needs To Do Something > is that right now it gives up if it sees large folios (because it was > written when there were two sizes of folio -- order 0 and PMD_ORDER). > Nobody has yet taken on making it turn order-N folios into PMD_ORDER > folios. Perhaps you'd like to do that? I was hoping the mTHP work for khugepaged (haven't checked the latest their yet) would add the necessary building block and adding file support would be trivial. I will check the latest there and see what we can do there sometime next year.
