Duperemove is a simple tool for finding duplicated extents and
submitting them for deduplication. When given a list of files it will
hash their contents on a block by block basis and compare those hashes
to each other, finding and categorizing extents that match each other.
When given the -d option, duperemove will submit those extents for
deduplication using the btrfs-extent-same ioctl.
