From owner-freebsd-questions Wed Oct 31 9:47: 4 2001 Delivered-To: freebsd-questions@freebsd.org Received: from root.com (root.com [209.102.106.178]) by hub.freebsd.org (Postfix) with ESMTP id ABBAE37B405 for ; Wed, 31 Oct 2001 09:46:59 -0800 (PST) Received: (from dg@localhost) by root.com (8.11.2/8.11.2) id f9VHhlk99582; Wed, 31 Oct 2001 09:43:47 -0800 (PST) (envelope-from dg) Date: Wed, 31 Oct 2001 09:43:47 -0800 From: David Greenman To: Kris Kennaway Cc: Ngoclan Vu , questions@FreeBSD.ORG Subject: Re: FreeBSD 1TB filesystem limitation Message-ID: <20011031094347.A99559@nexus.root.com> References: <20011031021107.A23867@xor.obsecurity.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20011031021107.A23867@xor.obsecurity.org>; from kris@obsecurity.org on Wed, Oct 31, 2001 at 02:11:08AM -0800 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG >On Tue, Oct 30, 2001 at 06:21:56PM -0800, Ngoclan Vu wrote: >> Hi, >> >> Do you have suggestions as to how to deal with the FreeBSD file system >> limitation of 1TB? Is it possible to get beyond this limitation? Are there >> other file system for FreeBSD that do not have this 1TB limitation. > >It's not a limitation in FreeBSD per se, it's a limitation in how you >built your filesystem. Read the newfs and tuning manpages and rebuild >your filesystem with e.g. a larger block and fragment size. Actually it is a limitation in FreeBSD. The 1TB limit isn't a filesystem limit, however, it's a limit on the maximum size of a disk device caused by disk block pointers (daddr_t) being 32 bit signed integers and physical disk blocks being 512 bytes large. 2 billion 512 byte blocks is 1TB. There is no way in FreeBSD to make physical disk block sizes different than 512 bytes. Fixing this requires making daddr_t larger and that affects huge chunks of the kernel. I would say that it's at least several man-months of work for someone who is very familiar with the code. -DG David Greenman Co-founder, The FreeBSD Project - http://www.freebsd.org President, TeraSolutions, Inc. - http://www.terasolutions.com Pave the road of life with opportunities. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message