Louis-Marie writes: > I also have a remark about backuppc pooling feature: I think the server > locally detects file duplicates by hashing them after download. As far > as I know, rsync should also be able to send some kind of hash from > remote host before download. Wouldn't it be possible to detect > duplicates using this hash before the file is downloaded? This would for > example save downloading files again when a user simply renames a > directory...
Rsync only efficiently transfers changes to files that have the same path. Rsync does not detect renamed files - it does a complete transfer in that case. (Some work was done patching rsync to do "fuzzy" matching to try to find some renamed files.) BackupPC uses the efficiency of rsync transfers, and then globally matches identical files. A renamed file will be verbatim transferred and then matched to the pool. If the rsync transfer determines the file is identical, BackupPC simply adds a hardlink. If the rsync transfer notices even a small change to a file, just the change will be transferred, but then BackupPC needs to reconstruct the full file to determined whether a match is in the pool. Craig ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ BackupPC-users mailing list [email protected] List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/
