From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chuck Campbell Subject: Re: disk fragmentation Date: Mon, 26 Apr 2004 12:08:57 -0500 Sender: linux-admin-owner@vger.kernel.org Message-ID: <20040426170857.GA5966@helium.inexs.com> References: <200404261018.35979.fluca1978@virgilio.it> Reply-To: campbell@accelinc.com Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <200404261018.35979.fluca1978@virgilio.it> List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Luca Ferrari Cc: linux-admin@vger.kernel.org On Mon, Apr 26, 2004 at 10:18:35AM +0200, Luca Ferrari wrote: > Hi, > I've got a simple question about disk use under windows and unix. While > windows sometimes requires a de-fragmentation of the disk, it seems as Linux > (and even Unix) does not. I believe this is due to a better defragmentation > alghoritm, but I'm not sure. Is there a daemon which does this transparently > or what? No, Unix file systems, in general, are designed to have less performance issues from fragmentation. They aren't as susceptible inherently to fragmentation problems. As a result, there aren't any defrag tools around that I know of. You can always build your own. A backup to tape will sequence all the files contiguously on tape/disk, and a subsequent restore will put them back that way. If you bother, do some benchmarks for a particular file i/o before and after and I doubt you'll see much difference, unless your disk is very, very nearly full. -chuck