- - Added the --append option that makes rsync append data onto files
- that are longer on the source than the destination (this includes new
- files).
-
- - Added the --min-size=SIZE option to exclude small files from the
- transfer.
-
- - Added the --compress-level option to allow you to set how aggressive
- rsync's compression should be (this option implies --compress).
-
- - Enhanced the parsing of the SIZE value for --min-size and --max-size
- to allow easy entry of multiples of 1000 (instead of just multiples
- of 1024) and off-by-one values too (e.g. --max-size=8mb-1).
-
- - The options --human-readable (-h) and --si change the output of the
- --stats and the end-of-run summary to be easier to read.
-
- - If lutimes() and/or lchmod() are around, use them to allow the
- preservation of attributes on symlinks.
-
- - The --link-dest option now affects symlinks and devices (when
- possible).
-
- - Improved the output of hard-linked and copied files when using
- --link-dest, --copy-dest, or --compare-dest.
+ - A new incremental-recursion algorithm is now used when rsync is talking
+ to another 3.0.0 version. This starts the transfer going more quickly
+ (before all the files have been found), and requires much less memory.
+ See the --recursive option in the manpage for some restrictions.
+
+ - The default --delete algorithm is now --delete-during when talking to a
+ 3.x rsync. This is a faster scan than using --delete-before (which is
+ the default when talking to older rsync versions), and is compatible
+ with the new incremental recursion mode.
+
+ - Added the --delete-delay option, which is a more efficient way to
+ delete files at the end of the transfer without needing a separate
+ delete pass.
+
+ - You may specify --max-delete=0 to a 3.0.0 client as long as the
+ receiving side is at least version 3.0.0. This means that you
+ can pull from an older rsync with this option, but pushing to an
+ older rsync will generate an error. *Be sure to never specify a 0
+ value to an older rsync client, or it will be silently ignored.*
+
+ - The --hard-link option now uses less memory on both the sending and
+ receiving side for all protocol versions. For protocol 30, the use
+ of a hashtable on the sending side allows us to more efficiently
+ convey to the receiver what files are linked together. This reduces
+ the amount of data sent over the socket by a considerable margin
+ (rather than adding more data), and limits the in-memory storage of
+ the device+inode information to just the sending side for the new
+ protocol 30, or to the receiving side when speaking an older protocol
+ (note that older rsync versions kept the device+inode information on
+ both sides).