PROPOSAL: --link-hash-dest, additional linking of files to their HASH values

[Helge Jensen]

I'm using the excellent --link-dest option on rsync to do every-day full 
backups of a number of servers. These servers share most of the 
file-system content, but of course has some variations.

In order to reduce the space used for each backup, I was thinking about 
linking all files in the backups to their hash in a separate directory, 
allowing only one storage of each file-value, reducing my backup-needs 
with ~5Gb per machince.

Further this would allow rysnc to represent moved files without any 
space-usage at all, for example rotated backups and user-moved files fit 
this description.

I realize, that there may be problems with file-system performance on 
such large directories, but that could probably be workarounded by using 
some prefix-subdirs.

For cleanup, one could find all the files in the --link-hash-dest 
directory with only 1 link.

Any comments?

-- 
Helge