Certainly sounds intriguing. From a ZFS standpoint, the easiest way to do this would be to take a snapshot on every txg - not sure how one would do it in a non-COW filesystem without inducing unacceptable overhead. This is an expansion of the 'user undo' functionality that's been discussed before, as it covers changes to a file, as opposed to just deleting it outright.
The hard part (besides the underlying filesystem implementation) is to how to administer this space. If I fill up my hard drive, does it start to take away from my backup space? Do I just set a backup size? Is it per-folder or per-filesystem? Do I have control over the behavior once the backup is full? And for non-GUI users, how does one access these other versions, and know how much space they're taking up? It also sounds like there is some higher level integration with their apps. For example, they describe dragging "backwards through time" in iPhoto. This needs some clear hooks to iPhoto so it knows when to refresh the visual content, etc. I doubt they actually rollback the whole filesystem - it's much more likely that they have hooks in the critical apps which know how to look for their "alternate" copie Hopefully we'll hear some more details about how this is implemented, as well as how they deal with the out-of-space edge conditions. - Eric On Mon, Aug 07, 2006 at 01:04:22PM -0500, Tao Chen wrote: > I am reading the live coverage of WWDC keynote here: > http://www.macrumorslive.com/web/ > > They talked about a new feature in OS X/Leopard: "Time Machine". > Does it sound like instant snapshot and rollback to you? > I don't know how else this can be implemented. > > 10:37 am with time machine, you can get those files back by > entering a date or time > 10:35 am ever had time where you work on a doc and you do a > save as and overwrote the wrong one? > 10:35 am coolest part - and reason we call it that > - whole new way of backing up files > 10:35 am backup to HD, or server > 10:35 am can restore everything, or just one file at a time > 10:34 am can be right where you were when the HD drive > 10:34 am automatically backs up mac you change a file, > it automatically backs up photos, music, documents, > files folder, everything then you can restore everything > 10:34 am plan to change all of that > Time Machine > 10:33 am how many use automated software to stay always backed up? > only 4% > > Tao > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss -- Eric Schrock, Solaris Kernel Development http://blogs.sun.com/eschrock _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss