From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shawn O. Pearce" <spearce@spearce.org>
Subject: Re: [PATCH 1/3] Lazily open pack index files on demand
Date: Sun, 27 May 2007 17:35:25 -0400
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Cc: Dana How <danahow@gmail.com>, Junio C Hamano <junkio@cox.net>,
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To: Nicolas Pitre <nico@cam.org>
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Nicolas Pitre <nico@cam.org> wrote:
> On Sat, 26 May 2007, Dana How wrote:
> 
> > On 5/26/07, Shawn O. Pearce <spearce@spearce.org> wrote:
> > > In pack v4 we're likely to move the SHA-1 table from the .idx file
> > > into the front of the .pack file.  This makes the .idx file hold
> > > only the offsets and the CRC checkums of each object.  If we start
> > > making a super index, we have to duplicate the SHA-1 table twice
> > > (once in the .pack, again in the super index).
> > 
> > Hmm, hopefully the SHA-1 table can go at the _end_
> > since with split packs that's the only time we know the number
> > of objects in the pack... ;-)
> 
> Hmmm good point to consider.

The problem with putting the SHA-1 table at the end of the pack is
it ruins the streaming for both unpack-objects and index-pack if
we were to ever use pack v4 as a transport format.  Or just try
to run a pack v4 packfile through unpack-objects, just locally,
say to extract megablobs.  ;-)

-- 
Shawn.