Re: [GIT PATCH] Selective diff-tree

From: Linus Torvalds <torvalds@osdl.org>
Date: Apr 24, 2005, 17:20 UTC
Message-ID: <Pine.LNX.4.58.0504241016390.15879@ppc970.osdl.org>
In-Reply-To: <7vbr84tyfd.fsf@assigned-by-dhcp.cox.net>

On Sun, 24 Apr 2005, Junio C Hamano wrote:

>
> Is either of you planning to do the same for diff-cache?

I wasn't. I don't think it's nearly as relevant for diff-cache, since diff-cache is never run thousands of times.

IOW, with diff-cache you can just do

	diff-cache <tree> | grep "interesting"

and you're done.

Diff-tree is different, simply because diff-tree is the way you find out which files changed between two revisions, so if you search for "when did this file change" you may well have to do _thousands_ of different diff-tree's. That's why pruning the diff-tree output is important: it makes diff-tree _much_ cheaper.

diff-cache usually doesn't make sense to do against more than one or two threes (the parent, and after a merge but before you commit maybe the parent_s_).

		Linus