From owner-freebsd-chat Sun Sep 7 23:27:15 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id XAA11357 for chat-outgoing; Sun, 7 Sep 1997 23:27:15 -0700 (PDT) Received: from genesis.atrad.adelaide.edu.au (genesis.atrad.adelaide.edu.au [129.127.96.120]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id XAA11308 for ; Sun, 7 Sep 1997 23:26:35 -0700 (PDT) Received: from word.smith.net.au (lot.atrad.adelaide.edu.au [203.20.121.21]) by genesis.atrad.adelaide.edu.au (8.8.5/8.7.3) with ESMTP id PAA24579 for ; Mon, 8 Sep 1997 15:56:23 +0930 (CST) Received: from word.smith.net.au (localhost.atrad.adelaide.edu.au [127.0.0.1]) by word.smith.net.au (8.8.7/8.8.5) with ESMTP id PAA01604; Mon, 8 Sep 1997 15:46:36 +1000 (EST) Message-Id: <199709080546.PAA01604@word.smith.net.au> X-Mailer: exmh version 2.0zeta 7/24/97 To: hcremean@vt.edu cc: Simon Shapiro , chat@freebsd.org Subject: Re: lousy disk perf. under cpu load (was IDE vs SCSI) In-reply-to: Your message of "Mon, 08 Sep 1997 01:32:27 -0400." <19970908013227.32344@wakky.dyn.ml.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 08 Sep 1997 15:46:35 +1000 From: Mike Smith Sender: owner-freebsd-chat@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > > PS: When did the first voice-coil-seek hard drives come out? This is a > question that's been bugging me for some time now... Linear or rotary actuator? The linear VC actuator probably predates the use of stepper motors; certainly some of the more impressive magnets in my collection started their lives in disk units. High-precision stepper motor controls are more complex than the linear displacement sensor approach that you use with a linear VC actuator too; it's the mechanicals and the space that made steppers cheaper, AFAIK. mike