That sounds like it would be an issue for anything. If the kernel knows that N pages need to be paged in, it should be able to optimize that behind the scenes

That sounds like it would be an issue for anything. If the kernel knows that N pages need to be paged in, it should be able to optimize that behind the scenes in whatever way is needed. I'll agree that mmap() would probably have issues with prediction there (other than basic readahead), but I would think that issuing a simple bulk read() call (or more likely an equivalent zero copy call; vread() if memory serves? Been too long) would give the kernel enough information to optimize bulk transfers. Small async reads will always be slow if done serially, but there's already "standard" scatter/gather calls that should let the kernel optimize that as well. In short, all but a truly naive application should be limited by the SSD or PCIe bandwidth before they ever hit issues like that if the kernel is optimizing correctly, and assuming that the application can predict its own needs.