From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Pitre <nico@fluxnic.net>
Subject: Re: git clone sending unneeded objects
Date: Sat, 26 Sep 2009 22:31:44 -0400 (EDT)
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Cc: Jason Merrill <jason@redhat.com>,
	Matthieu Moy <Matthieu.Moy@grenoble-inp.fr>,
	git@vger.kernel.org, Hin-Tak Leung <hintak.leung@gmail.com>
To: "Shawn O. Pearce" <spearce@spearce.org>
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On Sat, 26 Sep 2009, Shawn O. Pearce wrote:

> Nicolas Pitre <nico@fluxnic.net> wrote:
> > And even if the broken clone (before my patch) did pull everything from 
> > gcc.git, in the cloned repository those 410610 extra objects are 
> > considered as garbage because nothing actually reference them.  So even 
> > if you decide to fetch the extra branches that the initial clone didn't 
> > pick up, or if you do reference that repository with "garbage" objects 
> > for another clone to which you want to add those extra branches, git has 
> > no way to know that it already had access to those objects locally and 
> > "ungarbage" them as they aren't referenced.  Result is a useless fetch 
> > of 410610 objects that you already have, but that you weren't supposed 
> > to have in the first place.
> 
> Just to clarify a minor nit:
> 
> Actually, if those refs have not changed, quickfetch should kick in
> and realize that all 410610 objects are reachable locally without
> errors, permitting the client to avoid the object transfer.
> 
> However, if *ANY* of those refs were to change to something you
> don't actually have, quickfetch would fail, and we would need to
> fetch all 410610 objects.

Right.  But since we're talking about a git mirror for the gcc svn repo 
and gcc is a rather active project, the likelyhood of any ref to change 
at any time is rather high.


Nicolas