From owner-freebsd-questions@FreeBSD.ORG Thu Jan 27 21:33:45 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 D497716A4CE for ; Thu, 27 Jan 2005 21:33:45 +0000 (GMT) Received: from galilee.polands.org (CPE-24-208-53-189.new.rr.com [24.208.53.189]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1301643D41 for ; Thu, 27 Jan 2005 21:33:45 +0000 (GMT) (envelope-from djp@polands.org) Received: from jericho.polands.org (jericho.polands.org [172.16.1.35]) by galilee.polands.org (8.12.9/8.12.9) with ESMTP id j0RLXhRZ068604; Thu, 27 Jan 2005 15:33:43 -0600 (CST) (envelope-from djp@polands.org) Received: from jericho.polands.org (localhost [127.0.0.1]) by jericho.polands.org (8.13.1/8.13.1) with ESMTP id j0RLXhfX061979; Thu, 27 Jan 2005 15:33:43 -0600 (CST) (envelope-from djp@jericho.polands.org) Received: (from djp@localhost) by jericho.polands.org (8.13.1/8.13.1/Submit) id j0RLXhAR061978; Thu, 27 Jan 2005 15:33:43 -0600 (CST) (envelope-from djp) Date: Thu, 27 Jan 2005 15:33:43 -0600 From: Doug Poland To: Chad Morland Message-ID: <20050127213343.GA61034@polands.org> References: <8ca9329050127121428870c21@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8ca9329050127121428870c21@mail.gmail.com> User-Agent: Mutt/1.5.6i cc: questions@freebsd.org Subject: Re: RAID1, a failed disk and performance X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 27 Jan 2005 21:33:45 -0000 On Thu, Jan 27, 2005 at 03:14:46PM -0500, Chad Morland wrote: > What happens in terms of performance when a drive in a RAID1 system > fails? Will disk access be slower because it attempts to read/write to > a failed disk or will performance be faster because it doesn't need to > do half the work it usually does? I couldn't really find any online > resources that deal with performance levels when there are failed > drives present in a RAID array. > I recently set-up and tested a geom-based RAID1. When I pulled a hot-swap SATA drive from the server, I didn't notice any performance degradation. However, I must note that I wasn't running any monitoring software nor gathering empirical data. It's just my observation of the responsiveness of the system while one drive was gone. YMMV. -- Regards, Doug