<hansbkk <at> gmail.com> writes: > > Or even (forgive me please rabid BackupPC devotees) consider another > tool to handle those special-case files.
I've done a bit of investigation on this. I used rdiff, which is a command-line interface to the algorithm used by both rsync and rdiff-backup. It looks like this particular database backup is mostly the same, but updates -- block timestamps perhaps? -- are scattered throughout. rdiff delta ran extremely slow, and after having processed about 10% of the file, had generated a 400MB delta already, so probably would have wound up with a 4GB delta against the 20GB file. I don't know if rsync has particularly slow performance against block-type files where blocks remain similar but each block header changes, but that may be what's happening here. A 4GB .bz2 representation of this same data didn't have this problem, so I am going to test gzipping the file on the server and transferring that. > rdiff-backup is designed for exactly this type of scenario - very > large files that only change a little bit from one run to the next - I have used rdiff-backup myself for a number of years but for various reasons (chiefly performance) I don't think it's suitable for me here -- but thanks for the tip. -- John ------------------------------------------------------------------------------ Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)! Finally, a world-class log management solution at an even better price-free! Download using promo code Free_Logger_4_Dev2Dev. Offer expires February 28th, so secure your free ArcSight Logger TODAY! http://p.sf.net/sfu/arcsight-sfd2d _______________________________________________ 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/
