Re: git-gc "--aggressive" somewhat broken

[Nicolas Pitre <nico@cam.org>]

On Fri, 6 Jul 2007, Linus Torvalds wrote:

> 
> 
> On Fri, 6 Jul 2007, Linus Torvalds wrote:
> > 
> > If we want to be really aggressive, we migth decide to pass a new flag to 
> > pack-objects that does something closer to what "aggressive" was meant to 
> > do: it would use existing delta's if they exist, but _despite_ existing it 
> > could look if there are even better choices.
> 
> This is a totally untested patch that may or may not work.
> 
> The reason I say "may not work" is not just that I haven't really tested 
> it, it's also because I haven't thought it through very well.
> 
> In particular, does this possibly cause infinite loops of delta chains? 
> Probably. It would need code to explicitly make sure that we don't do 
> that, but I couldn't even convince myself as to why we might not hit that 
> case _already_ with delta re-use, so maybe there's something going that 
> protects us against it.

There is.

> Anyway, consider this a starting point for somebody else who wants to 
> really try to look into this.

This is a real teaser.  But I have real work to do if I want to leave on 
vacation this summer, and therefore I'll then be on vacation.  So if I 
end up looking at it myself it will be in September.


Nicolas