[rdiff-backup-users] Suggest feature --no-archive-if-no-changes

[Dominic]

As I understand it, every rdiff-backup run produces a record in the 
rdiff-backup repository. Many of my archives have source data which 
changes infrequently or in a few cases not at all, but rdiff-backup is 
run daily just in case. This means an accumulation of backup records 
which although they probably take up very little disk space, can greatly 
complicate understanding and retrieving data at a later date. For 
instance, archfs loads more and more slowly as the number of backup runs 
in the archive increases, and it creates an entry in the virtual 
directory structure for every backup of every file regardless of whether 
the file had changed or not.

I think it would be good if rdiff-backup had a switch something like 
--no-archive-if-no-changes which would mean that if there were no 
changes in the source data then nothing would be changed in the archive 
at all, and there would be no record of that rdiff-backup run.

Would this be helpful for others, and if so would it be easy for you to 
implement Andrew?

Dominic