[PATCH] gc --aggressive: make it really aggressive

[Nicolas Pitre]

On Thu, 6 Dec 2007, Theodore Tso wrote:

> Linus later pointed out that what we *really* should do is at some
> point was to change repack -f to potentially retry to find a better
> delta, but to reuse the existing delta if it was no worse.  That
> automatically does the right thing in the case where you had
> previously done a repack with --window=<large n> --depth=<large n>,
> but then later try using "gc --agressive", which ends up doing a worse
> job and throwing away the information from the previous repack with
> large window and depth sizes.  Unfortunately no one ever got around to
> implementing that.

I did start looking at it, but there are subtle issues to consider, such 
as making sure not to create delta loops.  Currently this is avoided by 
never involving already reused deltas in new delta chains, except for 
edge base objects.

IOW, this requires some head scratching which I didn't have the time for 
so far.


Nicolas