From owner-freebsd-hackers Tue Aug 28 0:23:11 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from robin.mail.pas.earthlink.net (robin.mail.pas.earthlink.net [207.217.120.65]) by hub.freebsd.org (Postfix) with ESMTP id 6B0D937B40A for ; Tue, 28 Aug 2001 00:23:02 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from mindspring.com (dialup-209.245.143.233.Dial1.SanJose1.Level3.net [209.245.143.233]) by robin.mail.pas.earthlink.net (8.11.5/8.9.3) with ESMTP id f7S7N0o23209; Tue, 28 Aug 2001 00:23:00 -0700 (PDT) Message-ID: <3B8B46FE.6829CB7E@mindspring.com> Date: Tue, 28 Aug 2001 00:23:42 -0700 From: Terry Lambert Reply-To: tlambert2@mindspring.com X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: John Kozubik Cc: hackers@freebsd.org Subject: Re: multi-channel firewire host adaptors available ? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG John Kozubik wrote: > Has anyone seen multi-channel (up to eight) firewire PCI host adaptors ? > We require full 400Mb throughput on each channel, simultaneously. Interesting... 64bit PCI * 66Mhz = 4,429,185,024 bit/S = 4,244 Mbit/S = 528MB/S ...burst rate. Sustained rate is about half that, so the ballpark is: 2,122 Mbit/S = 264 MB/S. Assuming "400Mb" is "400Mbit", you will be at most able to process a total of 5 channels worth of data simultaneously. If that's "400MB", well, expect to get only 2/3 of a single channel, or burst, up to 1 1/3 channels... PS: The most I have seen on a single card is 2... -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message