rsync + tar archive performance

[Bartlomiej Radziszewski]

http://pastebin.com/ehQ8nHTM

..where m4 it's original dir backup from other server, m4rsync (rsync 
-rv m4 m4rsync), m4cp (cp -r m4 m4cp)

> But is the data the same ? Because the filesizes are smaller for the second.
>
> Or are these something like filesystem-image files ? Maybe you stored them
> as sparse files ?
>
> Could that be the reason for the difference in speed ?
>