> - Add OpenBFS support, SSD, Transparent compression, Allocate-on- > flush, > Extents, Desfrag Online,Sparse files, Delayed allocation, Persistent > preallocation, and Journal checksumming like Btrfs and ext4 > http://kernelnewbies.org/Ext4 BFS has been using extents for a decade, we call them block_runs. One more thing Linux "invented" ;) The rest we can't really support without breaking the existing layout and bumping up the version number... François.