From owner-freebsd-doc@FreeBSD.ORG Thu Oct 16 01:16:02 2003 Return-Path: Delivered-To: freebsd-doc@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 60A1916A4B3 for ; Thu, 16 Oct 2003 01:16:02 -0700 (PDT) Received: from pittgoth.com (14.zlnp1.xdsl.nauticom.net [209.195.149.111]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6EE4443FAF for ; Thu, 16 Oct 2003 01:16:01 -0700 (PDT) (envelope-from trhodes@FreeBSD.org) Received: from localhost (bay1-20.fyi.net [206.80.153.20]) by pittgoth.com (8.12.9/8.12.9) with SMTP id h9G8Fkvd039067; Thu, 16 Oct 2003 04:15:52 -0400 (EDT) (envelope-from trhodes@FreeBSD.org) Date: Thu, 16 Oct 2003 03:46:35 -0400 From: Tom Rhodes To: Ken Smith Message-Id: <20031016034635.02278753.trhodes@FreeBSD.org> In-Reply-To: <20031015012650.GC15466@electra.cse.Buffalo.EDU> References: <20031015012650.GC15466@electra.cse.Buffalo.EDU> X-Mailer: Sylpheed version 0.9.6claws (GTK+ 1.2.10; i386-portbld-freebsd5.1) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit cc: freebsd-docs@FreeBSD.org Subject: Re: Second change to Architecture Manual X-BeenThere: freebsd-doc@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Documentation project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 16 Oct 2003 08:16:02 -0000 On Tue, 14 Oct 2003 21:26:50 -0400 Ken Smith wrote: > > This is a second change I was thinking might make a good addition > to the Architecture Manual. Virtually every book that talks about > UNIX devices describes character and block devices. Developers new > to FreeBSD sometimes wonder what happened to block devices. And a > lot of places in lots of manual pages, books, etc. still at least > slightly suggest there could be more than just Character devices. > > Is this worth adding? Thanks... > > --- chapter.sgml_orig Fri Oct 10 09:37:18 2003 > +++ chapter.sgml Tue Oct 14 21:21:07 2003 > @@ -527,6 +527,22 @@ > > > > + > + Block Devices (Are Gone) > + > + Developers familiar with other UNIX systems expect there to > + be a second type of device known as block devices. On those other > + UNIX systems block devices are associated with the buffer cache. > + Data blocks from block devices are buffered inside the kernel > + and filesystems get mounted on block devices. This improves > + I/O efficiency. &os; has shifted the management of the buffer > + cache away from block devices. It is associated it with the virtual > + memory system and vnode system used to keep track of open files inside > + the kernel. As a result &os; no longer needs block devices and they > + have been removed from the system. Only character devices remain. > + > + > + > > Network Drivers I think it would add value. I'm sure someone will read it, hell, I just read over it. You may want to use the &unix; entity, use 'file systems', and perhaps use a semicolon to 'hook' the last sentence to the previous. How does that sound? :) -- Tom Rhodes