Removing redundant packs

[Petr Baudis <pasky@ucw.cz>]

  Hi,

  before exporting whole repo.or.cz over rsync for mirroring, I would
like to clean up the worst repositories (esp. linux-2.6 repositories)
whose objects database looks absolutely horrible now.

  At the same time, I have to be careful not to prune all unreferenced
objects since they can be referenced in forks.

  How would you go about it? My idea was to do a fresh cummulative pack
of all referenced objects with

	git repack -a

and then remove packs that contain _only_ objects that are already in
the fresh pack. But I have trouble with the second step; a very naive
grep loop ran for about a day when I stopped it and it was nowhere near
the half of the packs yet. I didn't figure out how to make use of
git-pack-redundant either.

  Does anyone have any hints?

  Thanks!

-- 
				Petr "Pasky" Baudis
We don't know who it was that discovered water, but we're pretty sure
that it wasn't a fish.		-- Marshall McLuhan