ZFS is effectively log-structured. It's what the BSD 4.4 LFS wanted to be. In many ways the two are remarkably similar. ZFS merely solved the problems that h

ZFS is effectively log-structured. It's what the BSD 4.4 LFS wanted to be. In many ways the two are remarkably similar. ZFS merely solved the problems that had been left unsolved (like garbage collection / free space management), dropped the "all the blocks in a transaction must be contiguous" part, added the ZIL for speed, added a notion of volumes that contain multiple datasets, and reified snapshots. Log-structured and CoW are very closely related.