From: Brandon Casey <casey@nrlssc.navy.mil>
Date: Wed, 13 Jun 2007 23:07:29 GMT
Subject: Re: clarify git clone --local --shared --reference
Message-ID: <467078B1.8080104@nrlssc.navy.mil>
In-Reply-To: <20070608053750.GB18521@spearce.org>

Shawn O. Pearce wrote:
> Brandon Casey <casey@nrlssc.navy.mil> wrote:

>> The docs (git-repack.txt) seem to suggest that git-repack (without -d) 
>> does not delete any objects. And if -d is used, then at most objects 
>> already referenced in other packs will be deleted. This makes me think 
>> that repack is safe on the source repository.
> 
> You are correct that leaving off the '-d' won't delete objects.
> But a pack is created by listing the objects we need, and if we don't
> need the object in source, we don't include it into the new pack.
> 
> -a -d implies delete all packs that existed when we started the
> repack.  So if an object was in the old packfile, and we didn't
> copy it to the new packfile, it gets deleted.  ;-)

Ok. There is the connection I did not make. repack -d is NOT harmless, 
since a pack that contains only objects referenced in other packs and 
dangling unreferenced objects, will be deleted. Which will be all of the 
preexisting packs in the case of git-gc since as you mentioned it 
repacks using -a -d -l.

Thanks for taking the time.

-brandon