This type of ZFS replication / synchronization and rsync as well isn't at all similar to S3. As seiji posted, this is a fast diff'ing mechanism - identifying an

This type of ZFS replication / synchronization and rsync as well isn't at all similar to S3. As seiji posted, this is a fast diff'ing mechanism - identifying and trasmitting only what changed from one version of a file to the next, excelling at when files are system images or very large multi-gig or multi-terabyte files. With S3, I don't believe it has any ability to diff and/or store and transmit diffs - S3 is just a data store. ZFS replication / rsync is more for the use case where you want to make sure files on multiple sides of the data transfer equation are the same, and can pass diffs back and forth between them. Basically, if you need and only use S3 and file storage, this isn't want you want at all. The closest analogue is a binary git merge for very very very large files.