From owner-freebsd-questions@FreeBSD.ORG Tue Feb 1 20:56:45 2005 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9F0DF16A4D1 for ; Tue, 1 Feb 2005 20:56:45 +0000 (GMT) Received: from smtp.golden.net (smtp.golden.net [199.166.210.31]) by mx1.FreeBSD.org (Postfix) with ESMTP id 47BDD43D4C for ; Tue, 1 Feb 2005 20:56:45 +0000 (GMT) (envelope-from gldisater@gto.net) Received: from 183-114.speede.golden.net ([216.75.183.114]) by smtp.golden.net with esmtp (Exim 4.22) id 1Cw54m-000Bhl-8n; Tue, 01 Feb 2005 15:56:44 -0500 Message-ID: <41FFEE64.1010109@gto.net> Date: Tue, 01 Feb 2005 16:02:28 -0500 From: Jeremy Faulkner User-Agent: Mozilla Thunderbird 1.0 (X11/20041208) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Jim Pazarena References: <41FFDECF.3060901@ccstores.com> In-Reply-To: <41FFDECF.3060901@ccstores.com> X-Enigmail-Version: 0.89.5.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit cc: FreeBSD Questions Subject: Re: disk fragmentation X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: gldisater@gto.net List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 01 Feb 2005 20:56:45 -0000 Jim Pazarena wrote: > during the boot sequence, I routinely see a "% fragmentation message". > > It was my understanding that fragmentation doesn't occur on a Unix > (er FreeBSD) box.. > > It seems that there is a concept of fragmentation from the above > message, so, is there an "un-fragment" utility? > > Jim > No there is not a defragmenting program. Fragmentation is not a problem it is part of the normal operation of the filesystem. Data is stored in the filesystem in blocks, if a file does not have enough data to evenly fill all of its assigned blocks then the last block for the file is a fragment. The UFS filesystem will fill the fragment with new data when new data is added to the file. Some filesystems used by a redmond based company do not attempt to fill existing fragments, but simply add new blocks to the file so that a file could have more than one fragmented block. There are better descriptions of what is occurring in the archives, and presumably in textbooks that discuss filesystems. -- Jeremy Faulkner