On 30 May 2008, at 15:49, J.P. King wrote: > For _my_ purposes I'd be happy with zfs send/receive, if only it was > guaranteed to be compatible between versions. I agree that the > inability > to extract single files is an irritation - I am not sure why this is > anything more than an implementation detail, but I haven't gone into > it in > depth.
I would presume it is because zfs send/receive works at the block level, below the ZFS POSIX layer - i.e., below the filesystem level. I would guess that a stream is simply a list of the blocks that were modified between the two snapshots, suitable for "re-playing" on another pool. This means that the stream may not contain your entire file. An interesting point regarding this is that send/receive will be optimal in the case of small modifications to very large files, such as database files or large log files. The actual modified/appended blocks would be sent rather than the whole changed file. This may be an important point depending on your file modification patterns. Jonathan _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss