On 10/20/24 20:53, Kent Overstreet wrote: > On Sun, Oct 20, 2024 at 11:46:11AM -0700, Linus Torvalds wrote: >> On Sun, 20 Oct 2024 at 10:04, Kent Overstreet <kent.overstreet@xxxxxxxxx> wrote: >> > >> > But given that vmalloc() already supports > INT_MAX requests, and memory >> > sizes keep growing so 2GB is getting pretty small - I think it's time, >> > this is going to come up in other places sooner or later. >> >> No. >> >> If you need 2GB+ memory for filesystem operations, you fix your code. > > This is for journal replay, where we've got a big array of keys and we > need to sort them. > > The keys have to fit in memory (and had to fit in memory previously, for > them to be dirty in the journal); What if the disk is moved to a smaller system, should the fs still mount there? (I don't mean such a small system that it can't vmalloc() 2GB specifically, but in principle...) > this array is just _references_ to > those keys. > >> 2GB is more than you *can* allocate on 32-bit platforms, and even on >> 64-bit ones it is often quite a lot. > > This came up on a machine with 128GB of ram.