From mboxrd@z Thu Jan  1 00:00:00 1970
From: Luke Kenneth Casson Leighton <luke.leighton@gmail.com>
Subject: Re: Resumable clone/Gittorrent (again)
Date: Thu, 13 Jan 2011 11:39:05 +0000
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Cc: Nicolas Pitre <nico@fluxnic.net>,
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To: Nguyen Thai Ngoc Duy <pclouds@gmail.com>
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On Sun, Jan 9, 2011 at 5:48 PM, Nguyen Thai Ngoc Duy <pclouds@gmail.com=
> wrote:
> On Sun, Jan 9, 2011 at 8:55 PM, Luke Kenneth Casson Leighton
> <luke.leighton@gmail.com> wrote:
>> =C2=A0you still have to come up with a mapping from "chains" to "pie=
ces".
>> in the bittorrent protocol the mapping is done *entirely* implicitly
>> and algorithmically.
>
> Given a commit SHA-1, the mapping can be done algorithmically because
> the graph from the commit tip is fixed. Perhaps not mapping all at
> once, but as you have more pieces in the graph, you can map more.

 you're _sure_ about this?  what happens when new commits get added,
and change that graph?  are you _certain_ that you can write an
algorithm which is capable of generating exactly the same mapping,
even as more commits are added to the repository being mirrored, or,
does that situation not matter?

l.