From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: Change set based shallow clone
Date: Sun, 10 Sep 2006 22:27:26 -0700
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Cc: git@vger.kernel.org, Jakub Narebski <jnareb@gmail.com>
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To: Shawn Pearce <spearce@spearce.org>
In-Reply-To: <20060911024434.GA29368@spearce.org> (Shawn Pearce's message of
	"Sun, 10 Sep 2006 22:44:34 -0400")
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Shawn Pearce <spearce@spearce.org> writes:

> Jakub Narebski <jnareb@gmail.com> wrote:
>> Junio C Hamano wrote:
>> 
>> >  the impact of changing the
>> > one-file-per-ref implementation to something based on a single
>> > simple databasy file (e.g. gdbm, bdb, sqlite, ...)
>> 
>> One of the complaints against Subversion was that it use BerkeleyDB
>> (bdb) backend... but it was before it acquired fsfs interface. Perhaps
>> we could use it too.
>
> I'm against the latest Berkely DB (Sleepy Cat) implementations.
> Every time I've stored data in them or in applications which use
> them I've lost everything.  GNU dbm might not be too bad.  SQL Lite
> is overkill.
>...
> This is probably something that is easily solved by a simple fixed
> record format holding a 20 byte SHA1 (binary) and a fixed width null
> terminated string holding the ref name, with the records sorted
> by ref name.  Its yet another file format with yet another set of
> utilities needed but we pretty much have those (update-ref).

Yup.  That is one reasonable implementation of "single simple
databasy file" I suggested.  Or we could just borrow .git/info/refs
format.