From owner-freebsd-questions@FreeBSD.ORG Mon Jun 4 16:26:27 2007 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 6995116A46E for ; Mon, 4 Jun 2007 16:26:27 +0000 (UTC) (envelope-from r17fbsd@xxiii.com) Received: from cartman.xxiii.com (cartman.xxiii.com [208.62.177.45]) by mx1.freebsd.org (Postfix) with ESMTP id 1488A13C46C for ; Mon, 4 Jun 2007 16:26:26 +0000 (UTC) (envelope-from r17fbsd@xxiii.com) Received: from [172.23.23.190] (lan23.xxiii.com [208.62.177.50]) by cartman.xxiii.com (8.13.8/8.13.8) with ESMTP id l54EIYJ3040947; Mon, 4 Jun 2007 10:18:35 -0400 (EDT) (envelope-from r17fbsd@xxiii.com) Message-ID: <46641F40.8030508@xxiii.com> Date: Mon, 04 Jun 2007 10:18:40 -0400 From: Rob User-Agent: Thunderbird 1.5.0.12 (Windows/20070509) MIME-Version: 1.0 To: FreeBSD Questions References: <46630382.8010901@tundraware.com> <6.2.3.4.2.20070603232531.03dffe40@mailsvr.xxiii.com> <4663AFCC.6080508@tundraware.com> In-Reply-To: <4663AFCC.6080508@tundraware.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: tundra@tundraware.com Subject: Re: Strange Intel Mobo Behavior 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, 04 Jun 2007 16:26:27 -0000 Tim Daneliuk wrote: >> The ad6 drive is supposed to do SATA-300, but realistically, other >> bottlenecks dictate it's not going to get anywhere near the '150 speed, > > Could you comment a bit more on why you think this is so. I would > think that with modern processors and buses, a machine with light load > ought to be able to drive SATA-300, but I've never actuall tested for I was off on my initial assumptions. I thought the "150" was 150 Giga-bit/sec, or approx 15 Giga-byte, or 15000 MB/sec. Which is well above the PCI and other bus speeds it needs to travel through to get to the processor. But reading http://en.wikipedia.org/wiki/Serial_ATA it's 150 Mega-byte/sec. I think older ATA chipsets are part of the PCI bus, which at 32 bits * 33MHz, which is about a 132MB/sec bottleneck. I don't know enough about PCI-X, PCI-E and newer chipsets to know speeds & bottlenecks, so I'll just shut up now ;) But seems like > 100MBs should be within reach. -RW