From mboxrd@z Thu Jan 1 00:00:00 1970 From: "C. Scott Ananian" Subject: Re: [PATCH] add the ability to create and retrieve delta objects Date: Wed, 4 May 2005 12:12:38 -0400 (EDT) Message-ID: References: <200505030657.38309.alonz@nolaviz.org> <200505041156.19499.mason@suse.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: Nicolas Pitre , Linus Torvalds , Alon Ziv , git@vger.kernel.org X-From: git-owner@vger.kernel.org Wed May 04 18:08:03 2005 Return-path: Received: from vger.kernel.org ([12.107.209.244]) by ciao.gmane.org with esmtp (Exim 4.43) id 1DTMOz-0002Hn-Lp for gcvg-git@gmane.org; Wed, 04 May 2005 18:07:10 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261871AbVEDQNg (ORCPT ); Wed, 4 May 2005 12:13:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261912AbVEDQNg (ORCPT ); Wed, 4 May 2005 12:13:36 -0400 Received: from sincerity-forever.csail.mit.edu ([128.30.67.31]:19693 "EHLO sincerity-forever.csail.mit.edu") by vger.kernel.org with ESMTP id S261871AbVEDQNe (ORCPT ); Wed, 4 May 2005 12:13:34 -0400 Received: from catfish.lcs.mit.edu ([128.30.67.25] helo=cag.csail.mit.edu) by sincerity-forever.csail.mit.edu with esmtp (Exim 3.36 #1 (Debian)) id 1DTMUY-0005wf-00; Wed, 04 May 2005 12:12:54 -0400 To: Chris Mason In-Reply-To: <200505041156.19499.mason@suse.com> Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org On Wed, 4 May 2005, Chris Mason wrote: > 3) create a git-pack tool that can pack/unpack existing changesets,trees and > files, optionally adding/removing deltas. A 'git-pull' tool might be more use. I can imagine Linus maintaining his local tree uncompressed, but the 'kernel.org' tree set up to git-pull-delta from him every hour or whatever, so that the network-accessible version is always network-efficient. 'git-pack' would then simplify to a git-pull-delta from an existing local repository. Ideally, you'd also be able to git-pull from a network packed repository and (transparently) unpack and undelta-fy the pulled files as they're added to your local repo. This would keep Linus from accidentally getting packed files in his tree when he pulled from a maintainer's packed/delta-ed network-accessible tree. I'd also be interested in seeing the speed/space numbers for some other delta chain lengths between 1 and 16. Maybe some intermediate point is optimal. [Also, limiting delta chains to a certain number of other *packed* objects -- instead of just 'objects' -- might be an improvement. Right now you're packing entire commits together, right? Maybe defining a delta chain as 'N other commits max' might improve i/o performance, as you'd just have to keep N other unpacked files around, instead of an arbitrary number.] --scott SSBN 743 BOND ESGAIN SUMAC ZPSECANT MHCHAOS Castro Flintlock payment anthrax SCRANTON PLO MKNAOMI DNC AVBLIMP RUFUS Secretary AK-47 Noriega ( http://cscott.net/ )