From owner-freebsd-hackers Sat Jul 6 17:43:26 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 372B037B400 for ; Sat, 6 Jul 2002 17:43:20 -0700 (PDT) Received: from srv1.cosmo-project.de (srv1.cosmo-project.de [213.83.6.106]) by mx1.FreeBSD.org (Postfix) with ESMTP id E8B9A43E31 for ; Sat, 6 Jul 2002 17:43:18 -0700 (PDT) (envelope-from ticso@cicely5.cicely.de) Received: from cicely5.cicely.de (cicely5.cicely.de [IPv6:3ffe:400:8d0:301:200:92ff:fe9b:20e7]) (authenticated bits=0) by srv1.cosmo-project.de (8.12.3/8.12.3) with ESMTP id g670h9Ma018622 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=OK); Sun, 7 Jul 2002 02:43:12 +0200 (CEST) (envelope-from ticso@cicely5.cicely.de) Received: from cicely5.cicely.de (localhost [IPv6:::1]) by cicely5.cicely.de (8.12.1/8.12.1) with ESMTP id g670h7FJ046229 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Sun, 7 Jul 2002 02:43:08 +0200 (CEST)?g (envelope-from ticso@cicely5.cicely.de) Received: (from ticso@localhost) by cicely5.cicely.de (8.12.1/8.12.1/Submit) id g670h5nY046228; Sun, 7 Jul 2002 02:43:05 +0200 (CEST)?g (envelope-from ticso) Date: Sun, 7 Jul 2002 02:43:04 +0200 From: Bernd Walter To: Matthew Dillon Cc: Bernd Walter , Terry Lambert , Darren Pilgrim , ticso@cicely.de, freebsd-hackers@FreeBSD.ORG Subject: Re: How does swap work address spacewise? Message-ID: <20020707004304.GL23704@cicely5.cicely.de> Reply-To: ticso@cicely.de References: <20020705234126.GA12183@atrbg11.informatik.tu-muenchen.de> <3D2640A7.3EA2236B@pantherdragon.org> <20020706020656.GL48977@cicely5.cicely.de> <3D2762FE.9D9E0378@pantherdragon.org> <20020706220720.GG23704@cicely5.cicely.de> <3D277274.B5F3CE58@pantherdragon.org> <3D2776BE.A39A1110@mindspring.com> <20020706231346.GJ23704@cicely5.cicely.de> <200207062342.g66NgMri063859@apollo.backplane.com> <20020707001019.GK23704@cicely5.cicely.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20020707001019.GK23704@cicely5.cicely.de> X-Operating-System: FreeBSD cicely5.cicely.de 5.0-CURRENT i386 User-Agent: Mutt/1.5.1i Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sun, Jul 07, 2002 at 02:10:19AM +0200, Bernd Walter wrote: > On Sat, Jul 06, 2002 at 04:42:22PM -0700, Matthew Dillon wrote: > > Negative block numbers are used by UFS to represent the indirect blocks > > associated with a file, while positive block numbers represent the > > contents of the file. > > I never saw any negative block numbers in on-disc structures. > Now I wonder if it was just hidden behind macros. > What is the reason to handle it that way? > Do you have some code reference for homework? OK - I've found it used for incore data and understand why it's done. > > These are logical block numbers, which are fragment-sized (1K typically). > > So, 2^31 x 1K = 2TB. > > > > Physical block numbers are 512-byte sized, with a range of 2^32 > > in -stable. This also winds up being 2TB. So increasing the fragment > > size does not help in -stable. > > It's a proven fact that there is a 1T limit somewhere which was > explained with physical block numbers beeing signed. -- B.Walter COSMO-Project http://www.cosmo-project.de ticso@cicely.de Usergroup info@cosmo-project.de To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message