From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Pitre <nico@cam.org>
Subject: Re: git-index-pack really does suck..
Date: Tue, 03 Apr 2007 17:05:19 -0400 (EDT)
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Cc: Chris Lee <clee@kde.org>, Junio C Hamano <junkio@cox.net>,
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On Tue, 3 Apr 2007, Linus Torvalds wrote:

> All that extra memory is just for SHA1 commit ID information. 

I don't see where that might be.  The only thing that the paranoia check 
triggers is:

	foo = read_sha1_file(blah);
	memcmp(foo with bar);
	free(foo);

So where is that commit ID information actually stored when using 
read_sha1_file()?

> Btw, even if we don't have any of the objects, if you have tons and tons 
> of objects and do a "git pull", just the *lookup* of the nonexistent 
> objects will be expensive: first we won't find it in any pack, then we'll 
> look at the loose objects, and then we'll look int he pack *again* due to 
> the race avoidance. So looking up nonexistent objects is actually pretty 
> expensive.

Not if you consider that it is performed _while_ receiving (and waiting 
for) the pack data over the net in the normal case.


Nicolas