Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262850AbUC2NAm (ORCPT ); Mon, 29 Mar 2004 08:00:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262906AbUC2M7q (ORCPT ); Mon, 29 Mar 2004 07:59:46 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.31.123]:44687 "EHLO atrey.karlin.mff.cuni.cz") by vger.kernel.org with ESMTP id S262850AbUC2MaP (ORCPT ); Mon, 29 Mar 2004 07:30:15 -0500 Date: Mon, 29 Mar 2004 11:28:36 +0200 From: Pavel Machek To: Jamie Lokier Cc: "Eric W. Biederman" , =?iso-8859-2?Q?J=F6rn?= Engel , Davide Libenzi , "Patrick J. LoPresti" , Linux Kernel Mailing List Subject: Re: [PATCH] cowlinks v2 Message-ID: <20040329092835.GD1453@openzaurus.ucw.cz> References: <20040321181430.GB29440@wohnheim.fh-wedel.de> <20040325174942.GC11236@mail.shareable.org> <20040325194303.GE11236@mail.shareable.org> <20040327102828.GA21884@mail.shareable.org> <20040327214238.GA23893@mail.shareable.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040327214238.GA23893@mail.shareable.org> User-Agent: Mutt/1.3.27i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 977 Lines: 22 Hi! > > There are two possible implementations strategies for implementing > > cow files. You can either start as Jrn did with hardlinks, or you > > can start with symlinks. ... > There's a third implementation strategy. Since we're talking in all > cases about adding a new feature to the underlying filesystem, why not > implement separate inodes pointing to an underlying shared inode which > holds the data. (I think it was mentioned earlier in this thread). Actually, there's 4th strategy, too. You could implement sharing at block level. Block free bitmap would become bigger, but you could do some tricks to keep it at ~8 bits per block... -- 64 bytes from 195.113.31.123: icmp_seq=28 ttl=51 time=448769.1 ms - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/