From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-1?Q?P=E1draig_Brady?= Subject: Re: Finding hardlinks Date: Thu, 11 Jan 2007 10:07:13 +0000 Message-ID: <45A60C51.4050305@draigBrady.com> References: <20070105131235.GB4662@ucw.cz> <20070108112916.GB25857@elf.ucw.cz> <1168359985.7817.4.camel@localhost.localdomain> <20070109195310.GA10572@janus> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Steven Rostedt , Miklos Szeredi , pavel@ucw.cz, mikulas@artax.karlin.mff.cuni.cz, matthew@wil.cx, bhalevy@panasas.com, arjan@infradead.org, jaharkes@cs.cmu.edu, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, nfsv4@ietf.org Return-path: Received: from mail.station1.mxsweep.com ([212.147.136.149]:2899 "EHLO blue.mxsweep.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S965353AbXAKKRW (ORCPT ); Thu, 11 Jan 2007 05:17:22 -0500 To: Frank van Maarseveen In-Reply-To: <20070109195310.GA10572@janus> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org =46rank van Maarseveen wrote: > On Tue, Jan 09, 2007 at 11:26:25AM -0500, Steven Rostedt wrote: >> On Mon, 2007-01-08 at 13:00 +0100, Miklos Szeredi wrote: >> >>>> 50% probability of false positive on 4G files seems like very ugly >>>> design problem to me. >>> 4 billion files, each with more than one link is pretty far fetched= =2E >>> And anyway, filesystems can take steps to prevent collisions, as th= ey >>> do currently for 32bit st_ino, without serious difficulties >>> apparently. >> Maybe not 4 billion files, but you can get a large number of >1 link= ed >> files, when you copy full directories with "cp -rl". >=20 > Yes but "cp -rl" is typically done by _developers_ and they tend to > have a better understanding of this (uh, at least within linux contex= t > I hope so). I'm not really following this thread, but that's wrong. A lot of people use hardlinks to provide snapshot functionality. I.E. the following can be used to efficiently make snapshots: rsync /src/ /backup/today cp -al /backup/today /backup/$Date See also: http://www.dirvish.org/ http://www.rsnapshot.org/ http://igmus.org/code/ > Also, just adding hard-links doesn't increase the number of inodes. I don't think that was the point. P=E1draig. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html