From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: Preferring shallower deltas on repack
Date: Mon, 09 Jul 2007 09:39:44 -0700
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Cc: Brian Downing <bdowning@lavos.net>, git@vger.kernel.org
To: Nicolas Pitre <nico@cam.org>
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In-Reply-To: <alpine.LFD.0.999.0707090954550.26459@xanadu.home> (Nicolas
	Pitre's message of "Mon, 09 Jul 2007 11:58:06 -0400 (EDT)")
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Nicolas Pitre <nico@cam.org> writes:

> On Sun, 8 Jul 2007, Junio C Hamano wrote:
>
>> It would become worrysome (*BUT* infinitely more interesting)
>> once you start talking about a tradeoff between slightly larger
>> delta and much shallower depth.  Such a tradeoff, if done right,
>> would make a lot of sense, but I do not offhand think of a way
>> to strike a proper balance between them efficiently.
>
> We already do something similar to that with max_size being a function 
> of the delta depth.  ...

Yeah, we had a fun thread about that; I forgot about it until
now.

> OK here it is.  And results on the GIT repo and another patalogical test 
> repo I keep around are actually really nice!  Not only the pack itself 
> is a bit smaller, but the delta depth distribution as shown by 
> git-verify-pack -v is much nicer with the bulk of deltas in the low 
> depth end of the spectrum and no more peak at the max depth level.

Looks obviously correct.  Brian, it would be very interesting to
see what Nico's patch does to your dataset.