On Wed, Aug 30, 2006 at 07:51:45PM +0100, Dick Davies wrote: > On 30/08/06, Matthew Ahrens <[EMAIL PROTECTED]> wrote: > > >'zfs send' is *incredibly* faster than rsync. > > That's interesting. We had considered it as a replacement for a > certain task (publishing a master docroot to multiple webservers) > but a quick test with ~500Mb of data showed the zfs send/recv > to be about 5x slower than rsync for the initial copy. > > You're saying subsequent copies (zfs send -i?) should be faster?
Yes and no. Depends on the nature of the changes that have happened. Re-writing the same file contents would result in the whole file's contents appearing in the incremental ZFS backup, but the rsync overhead for synchronizing the same file would be minimal (just the size of the rsync checksum, which is proportional to the file size, but much smaller). ZFS tracks changes transactionally and block-wise. Whereas rsync detects changes and produces remove+insert deltas. So ZFS snapshots/zfs send -i and rsync are very different things, complementary things perhaps, but different. Nico -- _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
