Re: kernel.org and GIT tree rebuilding

From: Linus Torvalds <torvalds@osdl.org>
Date: Jun 26, 2005, 22:34 UTC
Message-ID: <Pine.LNX.4.58.0506261528020.19755@ppc970.osdl.org>
In-Reply-To: <Pine.LNX.4.58.0506261359370.19755@ppc970.osdl.org>

On Sun, 26 Jun 2005, Linus Torvalds wrote:

Show 5 quoted lines

> 
> (You can also sort by filename, if you want to try. I don't track
> filenames at all there and it's actually non-trivial to do, so that would
> require some new and pretty nasty code, but it's possible in _theory_ at
> least.)

Heh. It's actually very easy if you don't take the "name" too seriously, and you just pick some random one, namely the first one that was used to reach the entry.

Then, you might sort the objects on a hash based on the name, and get tons of cheap deltas close-by.

It is _uglee_, but hey, it's a heuristic, and it happens to work pretty well. It brought the kernel pack down to 59M even with just a small window of 10.

Thanks to Davide for making me think about this hack, although he talked about something much more proper (and harder) than this quick and ugly heuristic ;)

The main change is that "git-rev-list --objects" has been changed to show the name the object was reached through.

			Linus