Re: [PATCH] gc: do not warn about too many loose objects

> >> The basic problem here, at least for us, is that gc has enough
> >> information to know it could expunge some objects, but because of how
> >> it is structured in terms of several substeps (reflog expiration,
> >> repack, prune), the information is lost between the steps and it
> >> instead writes them out as unreachable objects.  If we could prune (or
> >> avoid exploding) loose objects that are only reachable from reflog
> >> entries that we are expiring, then the problem goes away for us.  (I
> >> totally understand that other repos may have enough unreachable
> >> objects for other reasons that Peff's suggestion to just pack up
> >> unreachable objects is still a really good idea.  But on its own, it
> >> seems like a waste since it's packing stuff that we know we could just
> >> expunge.)
> >
> > No, we should have expunged everything that could be during the "repack"
> > and "prune" steps. We feed the expiration time to repack, so that it
> > knows to drop objects entirely instead of exploding them loose.
> 
> Um, except it doesn't actually do that.  The testcase I provided shows
> that it leaves around 10000 objects that are totally deletable and
> were only previously referenced by reflog entries -- entries that gc
> removed without removing the corresponding objects.