On Tue, May 3, 2011 19:39, Rich Teer wrote: > I'm playing around with nearline backups using zfs send | zfs recv. > A full backup made this way takes quite a lot of time, so I was > wondering: after the initial copy, would using an incremental send > (zfs send -i) make the process much quick because only the stuff that > had changed between the previous snapshot and the current one be > copied? Is my understanding of incremental zfs send correct?
Yes, that works. In my setup, a full backup takes 6 hours (about 800GB of data to an external USB 2 drive), the incremental maybe 20 minutes even if I've added several gigabytes of images. > Also related to this is a performance question. My initial test involved > copying a 50 MB zfs file system to a new disk, which took 2.5 minutes > to complete. The strikes me as being a bit high for a mere 50 MB; > are my expectation realistic or is it just because of my very budget > concious set up? If so, where's the bottleneck? In addition to issues others have mentiond, the way incremental send works, it follows the order the blocks were written in rather than disk order, so that can sometimes be bad. -- David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
