From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: Git and GCC
Date: Thu, 06 Dec 2007 12:04:29 -0800
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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To: Jon Loeliger <jdl@freescale.com>
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Jon Loeliger <jdl@freescale.com> writes:

> On Thu, 2007-12-06 at 00:09, Linus Torvalds wrote:
>
>> Git also does delta-chains, but it does them a lot more "loosely". There 
>> is no fixed entity. Delta's are generated against any random other version 
>> that git deems to be a good delta candidate (with various fairly 
>> successful heursitics), and there are absolutely no hard grouping rules.
>
> I'd like to learn more about that.  Can someone point me to
> either more documentation on it?  In the absence of that,
> perhaps a pointer to the source code that implements it?

See Documentation/technical/pack-heuristics.txt,
but the document predates and does not talk about delta
reusing, which was covered here:

    http://thread.gmane.org/gmane.comp.version-control.git/16223/focus=16267

> I guess one question I posit is, would it be more accurate
> to think of this as a "delta net" in a weighted graph rather
> than a "delta chain"?

Yes.