From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932366AbWGEFkd (ORCPT ); Wed, 5 Jul 2006 01:40:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932386AbWGEFkc (ORCPT ); Wed, 5 Jul 2006 01:40:32 -0400 Received: from c-67-177-35-222.hsd1.ut.comcast.net ([67.177.35.222]:55172 "EHLO ns1.utah-nac.org") by vger.kernel.org with ESMTP id S932366AbWGEFkc (ORCPT ); Wed, 5 Jul 2006 01:40:32 -0400 Message-ID: <44AB5210.50501@wolfmountaingroup.com> Date: Tue, 04 Jul 2006 23:45:52 -0600 From: "Jeffrey V. Merkey" User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Fedora/1.7.8-2 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "H. Peter Anvin" CC: Bill Davidsen , Benny Amorsen , linux-kernel@vger.kernel.org Subject: Re: ext4 features References: <20060701163301.GB24570@cip.informatik.uni-erlangen.de> <20060701170729.GB8763@irc.pl> <20060701174716.GC24570@cip.informatik.uni-erlangen.de> <20060701181702.GC8763@irc.pl> <20060703202219.GA9707@aitel.hist.no> <20060703205523.GA17122@irc.pl> <1151960503.3108.55.camel@laptopd505.fenrus.org> <44A9904F.7060207@wolfmountaingroup.com> <20060703232547.2d54ab9b.diegocg@gmail.com> <44AB3E4C.2000407@tmr.com> <44AB4A68.90301@zytor.com> In-Reply-To: <44AB4A68.90301@zytor.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org H. Peter Anvin wrote: > Bill Davidsen wrote: > >>> >>> DC> Easily doable in userspace, why bother with kernel programming >>> >>> In userspace you can't automatically delete the files when the space >>> becomes needed. The LD_PRELOAD/glibc methods also have the >>> disadvantage of having to figure out where a file goes when it's >>> deleted, depending on which device it happens to reside on. Demanding >>> read access to /proc/mounts just to do rm could cause problems. >>> >>> Userspace has had 10 years to invent a good solution. If it was so >>> easy, it would probably have been done. >>> >> Actually, if it were so important it WOULD have been done. I suspect >> that the issue is not lack of a good solution, but lack of a good >> problem. The behavior you propose requires a lot of kernel >> cleverness, including make the inodes seem to go away, so the count >> is "right" for what the user sees. >> > > The real solution for it is snapshots. Peter, Explain what you are thinking here. What I proposed, I have already implemented in NetWare, it's very easy to do. Snapshotting is not complex for FS's but does require a lot of space for meta-data to manage it. EXT is not architecteced for something this complex. A simple hidden mv is much easier to do. Jeff > > -hpa > - > 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/ >