Ah, yes. That would indeed still be a chunk list, albeit one backed by mmap. I can of course be totally wrong, but I think the OP was wondering why you couldn'

Ah, yes. That would indeed still be a chunk list, albeit one backed by mmap. I can of course be totally wrong, but I think the OP was wondering why you couldn't simply mmap the entire file in place without managing any lists, trees, or any data structure except for a flat array representing the whole file.