We have recently upgraded a large number of Moodle sites from 1.9 to 2.2
After running the cron jobs for the upgraded sites for a few days we discovered that the space use on the server was growing dramatically.
What we've found is that in addition to the new Automated backups we also have older course backups on every course on every site - my guess is that they are the old Moodle 1.9 backups.
These are not being deleted by the auto backup job as old versions so we've effectively doubled the volume of backups being storred.
I'm unable to see the backups in the Moodle data directory as all the file names are hashed and following the conversion process the timestamps aren't as they were when the backups were run.
Is there anyway to either delete these en mass from the back end or from in moodle itself or alternatively to find records in the database that show which files the course backups relate to so I can remove db entries and the files to tidy these up?