From owner-freebsd-questions@FreeBSD.ORG Mon Feb 8 20:06:25 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9AA0C10656A8 for ; Mon, 8 Feb 2010 20:06:25 +0000 (UTC) (envelope-from jerrymc@gizmo.acns.msu.edu) Received: from gizmo.acns.msu.edu (gizmo.acns.msu.edu [35.8.1.43]) by mx1.freebsd.org (Postfix) with ESMTP id 3A5348FC14 for ; Mon, 8 Feb 2010 20:06:24 +0000 (UTC) Received: from gizmo.acns.msu.edu (localhost [127.0.0.1]) by gizmo.acns.msu.edu (8.13.6/8.13.6) with ESMTP id o18K4i1o058248; Mon, 8 Feb 2010 15:04:44 -0500 (EST) (envelope-from jerrymc@gizmo.acns.msu.edu) Received: (from jerrymc@localhost) by gizmo.acns.msu.edu (8.13.6/8.13.6/Submit) id o18K4i1l058247; Mon, 8 Feb 2010 15:04:44 -0500 (EST) (envelope-from jerrymc) Date: Mon, 8 Feb 2010 15:04:44 -0500 From: Jerry McAllister To: bf1783@gmail.com Message-ID: <20100208200444.GA58228@gizmo.acns.msu.edu> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.2i Cc: freebsd-questions@freebsd.org Subject: Re: Should root partition be first partition? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 08 Feb 2010 20:06:25 -0000 On Mon, Feb 08, 2010 at 02:37:30PM -0500, b. f. wrote: > > You can even > >leave gaps between partitions if you want, but that is pretty crazy > >since it just wastes some of the available space. > > > >There have been quite a lot of recommendations on how to lay out a disk > >for best performance, based on the observation that disk access times > >vary depending on how far away the data is from the spindle, and the > >expected usage patterns for the partition. Like any such advice, it > >has tended to become less valid over time. Modern disks really don't > >have any physical meaning to the Cylinder/Head/Sector style addressing > >schemes[*] nowadays -- and you're pretty much bound to be using LBA > >style addressing anyhow. Also, machines nowadays have so much RAM that > >(a) swap is hardly ever used and (b) access to popular files is > >frequently answered out of VM caches rathe than needing disk IO. > > > Layout is still important, and leaving some blank space may not be so > crazy. Here I'm thinking not so much of ordering (although one would > probably be best served by the recommended default ordering), but of > alignment, size, raid/stripe/concat configuration, and file system > block and fragment size selection. Witness the (as much as tenfold) > performance difference from simple changes, highlighted in the recent > thread entitled 'File system blocks alignment' on freebsd-arch@ during > December 2009 - January 2010, beginning with: > > http://lists.freebsd.org/pipermail/freebsd-arch/2009-December/009770.html > > If you're laying out a new disk, you may as well take a few minutes > and get the most out of it, even if you're not going to invest in a > lot of new hardware. The system nowdays does all that figuring for you and manages boundaries reasonably. ////jerry > > b. > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org"