From: Duy Nguyen <pclouds@gmail.com>
Date: Mon, 16 Feb 2015 10:48:28 GMT
Subject: Re: Pack v4 again..
Message-ID: <CACsJy8AP88yX39QSyF2nN-01TN=7-0rKc==ncSua14_GM4s+Fg@mail.gmail.com>
In-Reply-To: <20150216064537.GF32381@peff.net>

On Mon, Feb 16, 2015 at 1:45 PM, Jeff King <peff@peff.net> wrote:
> Somewhat related to this, I was playing this weekend with the idea of
> generating fast tree diffs from our on-disk deltas. That is, given a
> base tree and a binary delta against it, could I reliably reproduce a
> diff (one way or the other) in O(size of diff), rather than O(size of
> tree)?

If you add a "delta" base cache for v4 trees to avoid the recursion
issue Nico mentioned, you effectively have a "diff" that aligns at
tree entry boundaries. The v4 tree encoding will become just another
delta format from this perspective. I'm very tempted to just go with
this to take advantage of v4 SHA-1 encoding, ident and path encoding..
-- 
Duy