From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: pack v4 status
Date: Tue, 27 Feb 2007 14:36:05 -0800
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	"Shawn O. Pearce" <spearce@spearce.org>, git@vger.kernel.org
To: Nicolas Pitre <nico@cam.org>
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	Pitre's message of "Tue, 27 Feb 2007 17:32:00 -0500 (EST)")
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Nicolas Pitre <nico@cam.org> writes:

> On Tue, 27 Feb 2007, Linus Torvalds wrote:
>
>> On Tue, 27 Feb 2007, Shawn O. Pearce wrote:
>> >  ...
>> > All trees are then converted to use a 22 byte record format:
>> > 
>> >   - 2 byte network byte order index into the string pool
>> >   - 20 byte SHA-1
>> 
>> Umm. Am I missing something, or is this totally braindamaged?
>> 
>> Are you really expecting there to never be more than 64k basenames? Trust 
>> me, that's a totally broken assumption. Anything that tracks generated 
>> stuff will _easily_ have several tens of thousands of random filenames 
>> even in a single tree, much less over the whole history of the repository.
>
> The idea is to deal with only tree objects containing the 64K most 
> frequently used base names and fall back to the current tree object 
> encoding for objects that couldn't be represented that way.

Ah, I was wondering the same thing as Linus after seeing shawn
talked about the 2-byte prefix on #git. Falling back to an
alternate encoding for rarer cases makes sense.