From owner-aic7xxx Fri Aug 14 15:42:24 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id PAA04008 for aic7xxx-outgoing; Fri, 14 Aug 1998 15:42:24 -0700 (PDT) (envelope-from owner-aic7xxx@FreeBSD.ORG) Received: from pluto.plutotech.com (mail.plutotech.com [206.168.67.137]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id PAA03889 for ; Fri, 14 Aug 1998 15:41:50 -0700 (PDT) (envelope-from gibbs@plutotech.com) Received: from narnia.plutotech.com (narnia.plutotech.com [206.168.67.130]) by pluto.plutotech.com (8.8.7/8.8.5) with ESMTP id QAA05851; Fri, 14 Aug 1998 16:40:24 -0600 (MDT) Message-Id: <199808142240.QAA05851@pluto.plutotech.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Matthew Jacob cc: "Justin T. Gibbs" , Ross Harvey , matti.aarnio@sonera.fi, aic7xxx@FreeBSD.ORG Subject: Re: AHA2790UW has speed-limit problems ? In-reply-to: Your message of "Fri, 14 Aug 1998 15:28:07 PDT." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 14 Aug 1998 16:34:39 -0600 From: "Justin T. Gibbs" Sender: owner-aic7xxx@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > >It's exactly this kind of discussion that has encouraged me to think >that Fibre Channel is a better technology when you're getting to these >speeds. The cost differential between this and parallel SCSI is getting >to be pretty small. I wish IBM hadn't botched the marketing of SSA. It's so much nicer than Fiber Channel. The concern we have here at Pluto about Fiber Channel is the power cost. We couldn't put 20 fiber channel drives into our system without bumping up to much more expensive, larger capacity, power supplies. There is also the fault tolerance issue and expense. We're single target/ single initiator so we can "play to air" even if a drive hangs on the wire. With SE/LVD SCSI, we can do this for ~$20 per SCSI HA chip. SSA would have solved this problem with it's dual port nature without forcing us to a single controller per drive configuration, but with fiber channel, you have no choice. I can't imagine being able to build a cost effective single initiator/single target system with fiber channel. The tranceiver cost alone would kill us. -- Justin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe aic7xxx" in the body of the message