Decius wrote: k wrote:
[ Anyone else recall me proposing just such a utility, oh, say, a month or 2 ago? Yeah. Beat to the punch. Guess I'll be paying Apple come spring. *sigh* -k]
Well, I recall such a utility being a core feature of Plan 9. However, I think I'd rather use hard drive space for media than for revision control on everything. They need to get disk sizes way, way out of the range of what normal people actually need in order to make this practical.
In my vision, only the most recent n revisions (by revision or disk usage or whatever, I hadn't gotten that far) were kept locally. A meta data store was maintained locally for all of the history, but the actual data were stored offline on a separate disk or network storage via periodic syncs. That way you get a hybrid system in which all files are versioned, your whole disk isn't being filled with the diffs, but, say, a weeks worth or so would be present. I though that provided a good balance between the "OH FUCK I SHOULDN'T HAVE DELETED THAT" mode of use and the "OH FUCK MY ENTIRE SYSTEM IS FUBAR" mode of use. I also envisioned a checkpointing mechanism in which every nth revision (again, n being undefined, as yet) was a full copy, not a diff to improve performance on restore and permit eventual phase out of all the intermediate versions, if desired. As it stands, local versioning is nice, but it's not a backup at all... if you have a head crash, you still lose everything. I'm certain this isn't lost on the apple engineers, so perhaps the final version will incorporate what I've said (or something better still). I'm also curious how smart the include/exclude logic is. It's one thing to diff text files. It's quite another to try and do the same thing for, say, an iMovie or iDVD project in which several multi-GB files are getting tossed about. Or my 150 GB iTunes library... is it smart enough to deal with that? In the meantime, I have too much media to store it locally on my laptop anyhow, so i don't even bother trying. I'm quite looking forward to trying out Time Machine. Also, I hadn't realized this was proposed back in the plan-9 days... though it's not terribly surprising. There aren't *that* many new ideas possible, and I'm not terribly likely to have one, all in all. -k] | 
