From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jon Smirl" Subject: Re: Git and GCC Date: Thu, 6 Dec 2007 01:47:54 -0500 Message-ID: <9e4733910712052247x116cabb4q48ebafffb93f7e03@mail.gmail.com> References: <4aca3dc20712051947t5fbbb383ua1727c652eb25d7e@mail.gmail.com> <20071205.202047.58135920.davem@davemloft.net> <4aca3dc20712052032n521c344cla07a5df1f2c26cb8@mail.gmail.com> <20071205.204848.227521641.davem@davemloft.net> <4aca3dc20712052111o730f6fb6h7a329ee811a70f28@mail.gmail.com> <1196918132.10408.85.camel@brick> <4aca3dc20712052117j3ef5cf99y848d4962ae8ddf33@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "Harvey Harrison" , "David Miller" , ismail@pardus.org.tr, gcc@gcc.gnu.org, git@vger.kernel.org To: "Daniel Berlin" X-From: git-owner@vger.kernel.org Thu Dec 06 07:48:16 2007 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1J0AWt-0003Rj-UM for gcvg-git-2@gmane.org; Thu, 06 Dec 2007 07:48:16 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752854AbXLFGr4 (ORCPT ); Thu, 6 Dec 2007 01:47:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752827AbXLFGrz (ORCPT ); Thu, 6 Dec 2007 01:47:55 -0500 Received: from wa-out-1112.google.com ([209.85.146.176]:64959 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752710AbXLFGrz (ORCPT ); Thu, 6 Dec 2007 01:47:55 -0500 Received: by wa-out-1112.google.com with SMTP id v27so264628wah for ; Wed, 05 Dec 2007 22:47:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=c6DVAxuVRu/oeueRi7bolVurB86ORMebV7yFgb0C+Zs=; b=qNNfXohHgXKcoTfQCqg6jeA6koEZsqUub3vi9yVTp1Elrhaa0LNhJbOcdsIYAu8WJwcBxSHmCEaC9F8BQgrD3Om7QAWCaEKOdHBQwx8fLq27jKSR8gK8Jdb2vMLlOGld1bbF7MWB3ScxwCOC/PEj/9kIUkP02ictkFTD4bLsB3A= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Bh6eOmbiMatmVHt07xIhevw2ugH9hHd3dNqPrhjPfV5Kbq23AcKKQXpHKRn7EtOYrhD1ccKSt9QVReJj/AgDS1I0XGmIjVGRJSjpd+60IpULp7549BV/wg2fOs5HQwfcwSispD/wO5ult8kBvYOPMav2q+ZvKRDnvW+exuRrILY= Received: by 10.114.73.1 with SMTP id v1mr510151waa.1196923674468; Wed, 05 Dec 2007 22:47:54 -0800 (PST) Received: by 10.114.208.17 with HTTP; Wed, 5 Dec 2007 22:47:54 -0800 (PST) In-Reply-To: <4aca3dc20712052117j3ef5cf99y848d4962ae8ddf33@mail.gmail.com> Content-Disposition: inline Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On 12/6/07, Daniel Berlin wrote: > > While you won't get the git svn metadata if you clone the infradead > > repo, it can be recreated on the fly by git svn if you want to start > > commiting directly to gcc svn. > > > I will give this a try :) Back when I was working on the Mozilla repository we were able to convert the full 4GB CVS repository complete with all history into a 450MB pack file. That work is where the git-fastimport tool came from. But it took a month of messing with the import tools to achieve this and Mozilla still chose another VCS (mainly because of poor Windows support in git). Like Linus says, this type of command will yield the smallest pack file: git repack -a -d --depth=250 --window=250 I do agree that importing multi-gigabyte repositories is not a daily occurrence nor a turn-key operation. There are significant issues when translating from one VCS to another. The lack of global branch tracking in CVS causes extreme problems on import. Hand editing of CVS files also caused endless trouble. The key to converting repositories of this size is RAM. 4GB minimum, more would be better. git-repack is not multi-threaded. There were a few attempts at making it multi-threaded but none were too successful. If I remember right, with loads of RAM, a repack on a 450MB repository was taking about five hours on a 2.8Ghz Core2. But this is something you only have to do once for the import. Later repacks will reuse the original deltas. -- Jon Smirl jonsmirl@gmail.com