From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: git-index-pack really does suck..
Date: Tue, 03 Apr 2007 15:31:36 -0700
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Cc: "Shawn O. Pearce" <spearce@spearce.org>,
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To: Linus Torvalds <torvalds@linux-foundation.org>
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	(Linus Torvalds's message of "Tue, 3 Apr 2007 14:28:22 -0700 (PDT)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> Side note: with "alternates" files, you might well *always* have the 
> objects. If you do
>
> 	git clone -l -s ...
>
> to create various branches, and then pull between them, you'll actually 
> end up in the situation that you'll always find the objects and get back 
> to the really expensive case..

Ah, that's true.  If you "git clone -l -s A B", create new
objects in A and pull from B, the transfer would not exclude
new objects as they are not visible from B's refs.

In that scenario, the keep-pack behaviour is already worse than
the unpack-objects behaviour.  The former creates a packfile
that duplicates objects that are in A while the latter, although
expensive, ends up doing nothing.

I wonder if we can have a backdoor to avoid any object transfer
in such a case to begin with...