From owner-freebsd-hackers Tue Jul 16 10:14:45 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id KAA13730 for hackers-outgoing; Tue, 16 Jul 1996 10:14:45 -0700 (PDT) Received: from MindBender.HeadCandy.com (root@mindbender.headcandy.com [199.238.225.168]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id KAA13715 for ; Tue, 16 Jul 1996 10:14:41 -0700 (PDT) Received: from localhost.HeadCandy.com (michaelv@localhost.HeadCandy.com [127.0.0.1]) by MindBender.HeadCandy.com (8.7.5/8.7.3) with SMTP id KAA23015; Tue, 16 Jul 1996 10:14:14 -0700 (PDT) Message-Id: <199607161714.KAA23015@MindBender.HeadCandy.com> X-Authentication-Warning: MindBender.HeadCandy.com: Host michaelv@localhost.HeadCandy.com [127.0.0.1] didn't use HELO protocol To: "Jordan K. Hubbard" cc: Jason Thorpe , dunn@harborcom.net, "'hackers@FreeBSD.org'" Subject: Re: mitsumi CD-ROM In-reply-to: Your message of Tue, 16 Jul 96 10:01:57 -0700. <20634.837536517@time.cdrom.com> Date: Tue, 16 Jul 1996 10:14:14 -0700 From: "Michael L. VanLoon -- HeadCandy.com" Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk >> Why? 8x on a IDE CD-ROM is 8x a "standard" (cough) IDE CD-ROM, which in >> my experience, is roughly equivalent to a 4x SCSI CD-ROM :-) >Hmmm. An interesting point. :-) Actually, it's *supposed* to mean 8x the original CD-ROM transfer speed, which is dictated by the speed the drive spins. 1x is 150KB/s. 8x is 1.2MB/s. It really is irrespective of the interface. HOWEVER, that is only a small part of the equation. The speed multiplier of the drive has no real correlation to the seek speed of the drive, and all CD-ROMs have slow seek times (some much slower than others, of course). So, it won't matter if your drive is 2x or 8x if it spends 80% of its time seeking. The only place that much extra speed becomes really useful is if the drive is able to stream the data in from sequential tracks, such as if a multi-media file was layed on the CD-ROM in a known sequential fashion. Otherwise, if you're spending 200ms average, per seek, and you're accessing a lot of files all over the disk, you might as well have a 2x SCSI drive, save a little money, and get something that doesn't dominate your CPU. That's how I understand it anyway. Besides, most of those newer IDE CD-ROMs I've seen on the market are so cheap as to basically be disposable. The build quality is just really awful in a lot of them. ----------------------------------------------------------------------------- Michael L. VanLoon michaelv@HeadCandy.com --< Free your mind and your machine -- NetBSD free un*x >-- NetBSD working ports: 386+PC, Mac 68k, Amiga, Atari 68k, HP300, Sun3, Sun4/4c/4m, DEC MIPS, DEC Alpha, PC532, VAX, MVME68k, arm32... NetBSD ports in progress: PICA, others... Roll your own Internet access -- Seattle People's Internet cooperative. If you're in the Seattle area, ask me how. -----------------------------------------------------------------------------