From owner-freebsd-current@FreeBSD.ORG Fri Jan 26 15:37:14 2007 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id E0CED16A404; Fri, 26 Jan 2007 15:37:14 +0000 (UTC) (envelope-from hselasky@c2i.net) Received: from swip.net (mailfe09.swip.net [212.247.155.1]) by mx1.freebsd.org (Postfix) with ESMTP id 2DB8A13C483; Fri, 26 Jan 2007 15:37:13 +0000 (UTC) (envelope-from hselasky@c2i.net) X-Cloudmark-Score: 0.000000 [] Received: from [193.217.102.48] (account mc467741@c2i.net HELO [10.0.0.249]) by mailfe09.swip.net (CommuniGate Pro SMTP 5.0.12) with ESMTPA id 225692775; Fri, 26 Jan 2007 15:37:11 +0100 From: Hans Petter Selasky To: freebsd-current@freebsd.org Date: Fri, 26 Jan 2007 15:36:48 +0100 User-Agent: KMail/1.9.5 References: <20070125.192448.-432840241.imp@bsdimp.com> <200701261341.03742.shoesoft@gmx.net> In-Reply-To: <200701261341.03742.shoesoft@gmx.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200701261536.48893.hselasky@c2i.net> Cc: Alexey Karagodov , Stefan Ehmann Subject: Re: Interesting speed benchmarks X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Jan 2007 15:37:15 -0000 On Friday 26 January 2007 13:41, Stefan Ehmann wrote: > On Friday 26 January 2007 13:35, Andrew Pantyukhin wrote: > > On 1/26/07, Stefan Ehmann wrote: > > > On Friday 26 January 2007 11:00, Alexey Karagodov wrote: > > > > what manufacturer says about usb speeds? > > > > that is the question > > > > > > Well, "up to 56MB/s" which is pretty much full USB2 speed. It is called high speed USB, and it can go up 53 MB/s with a payload of 512 bytes per packet according to "Table 5-10. High-speed Bulk Transaction Limits" in the USB 2.0 specification. The table does not say anything about whether this include bit-stuffing or not. If bit stuffing is not included, then you have to divide this value by 1.20 approximately for the worst case, all 1's. 53 MB/s div 1.20 = 44 MB/s. > > > > > > But writing it on the box doesn't mean the speed can actually be > > > reached. > > > > > > Benchmarking on windows might be interesting, but I don't know how to > > > measure raw disk io on windows. > > > > Format the disk, copy a large file to/from it, divide > > its size by time spent, add the word "approximately" :-) > > I'd rather not format a drive with my backups and other stuff on it :-) Results with the new USB stack*: Changing the interrupt delay from 2 microframes to 1 microframe gave me 2MBytes more per second on the EHCI controller. I connected two high speed "umass" capable devices to the same EHCI controller on my computer, and did a "dd" on both devices at the same time, with a block size of 131072 bytes. The one device transferred 22 MB/s. The other device transferred 16 MB/s. Summed up this yields 38 MB/s. Used alone these devices can transfer 27 MB/s and 20 MB/s. It seems clear that the EHCI controller is saturated at 38 MB/s. %dmesg |grep ehci ehci0: mem 0xe0100000-0xe01003ff irq 10 at device 29.7 on pci0 usb3: on ehci0 % --HPS * http://www.turbocat.net/~hselasky/usb4bsd or see the FreeBSD-perforce USB project.