>I dont know much about compression and how it all works, so I was thinking
>that if the majority of the archive was the same, and say they only patched
>up one or two files, then the compressed data would be the same or very
>similar for the files that didn't change. That was the theory I was thinking
>on.. Am I wrong?
If you are using Burroughs-Wheeler transform with fixed block size followed by
a compression scheme, as in bzip2, and the source code changes but its length
stays the same, various bytes scattered throughout that block will change.
There is a 1/8 chance that the next block, if there is one, will land on the
same byte boundary, in which case rsync will have something to work with.
If you are using Lempel-Ziv or Welch compression, any time after the change
that a sequence of bytes for which a token was made for the changed area in
either version occurs will result in a different token.
phma
