From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Woodhouse Subject: Re: WARNING! Object DB conversion (was Re: [PATCH] write-tree performance problems) Date: Thu, 21 Apr 2005 00:13:48 +1000 Message-ID: <1114006429.5877.42.camel@localhost.localdomain> References: <200504191250.10286.mason@suse.com> <200504191708.23536.mason@suse.com> <200504192049.21947.mason@suse.com> <42660708.60109@zytor.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: "H. Peter Anvin" , Git Mailing List , Chris Mason X-From: git-owner@vger.kernel.org Wed Apr 20 16:12:09 2005 Return-path: Received: from vger.kernel.org ([12.107.209.244]) by ciao.gmane.org with esmtp (Exim 4.43) id 1DOFuU-0002de-8V for gcvg-git@gmane.org; Wed, 20 Apr 2005 16:10:35 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261627AbVDTOOq (ORCPT ); Wed, 20 Apr 2005 10:14:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261638AbVDTOOq (ORCPT ); Wed, 20 Apr 2005 10:14:46 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:20887 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S261627AbVDTOOo (ORCPT ); Wed, 20 Apr 2005 10:14:44 -0400 Received: from [203.53.50.91] (helo=[172.18.240.72]) by pentafluge.infradead.org with esmtpsa (Exim 4.43 #1 (Red Hat Linux)) id 1DOFyM-0000HX-Tj; Wed, 20 Apr 2005 15:14:38 +0100 To: Linus Torvalds In-Reply-To: X-Mailer: Evolution 2.2.2 (2.2.2-1) X-Spam-Score: 0.0 (/) X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org On Wed, 2005-04-20 at 02:08 -0700, Linus Torvalds wrote: > I converted my git archives (kernel and git itself) to do the SHA1 > hash _before_ the compression phase. I'm happy to see that -- because I'm going to be asking you to make another change which will also require a simple repository conversion. We are working on getting the complete history since 2.4.0 into git form. When it's done and checked (which should be RSN) I'd like you to edit the first commit object in your tree -- the import of 2.6.12-rc2, and give it a parent. That parent will be the sha1 hash of the 2.6.12-rc2 commit in the newly-provided history, and of course will change the sha1 hash of your first commit, and all subsequent commits. We'll provide a tool to do that, of course. The history itself will be absent from your tree. Obviously we'll need to make sure that the tools can cope with an absentee parent, probably by just treating that case as if no parent exists. That won't be hard, it'll be useful for people to prune their trees of unwanted older history in the general case too. That history won't be lost or undone -- it'll just be archived elsewhere. The reason for doing this is that without it, we can't ever have a full history actually connected to the current trees. There'd always be a break at 2.6.12-rc2, at which point you'd have to switch to an entirely different git repository. -- dwmw2