No, I have not actually tested it yet, but according to my research the current state of btrfs send/receive is this: 1. btrfs send streams the files (i.e. it d

No, I have not actually tested it yet, but according to my research the current state of btrfs send/receive is this: 1. btrfs send streams the files (i.e. it decompresseses files that are compressed on disk) 2. The send stream (optionally) is compressed 3. btrfs receive (optionally) recompresses data into the destination If you have a large dataset and take the time to use one of the slower compression algorithms/settings this means that you have to wait for that compression to happen all over again at the destination. (you could have different compression settings on the two btrfs filesystems, btrfs send/receive is one of the ways for migrating data between these settings)