From owner-freebsd-hackers@FreeBSD.ORG Wed Jan 16 12:48:23 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id DF75216A41A for ; Wed, 16 Jan 2008 12:48:23 +0000 (UTC) (envelope-from ticso@cicely12.cicely.de) Received: from raven.bwct.de (raven.bwct.de [85.159.14.73]) by mx1.freebsd.org (Postfix) with ESMTP id 6844913C459 for ; Wed, 16 Jan 2008 12:48:23 +0000 (UTC) (envelope-from ticso@cicely12.cicely.de) Received: from cicely5.cicely.de ([10.1.1.7]) by raven.bwct.de (8.13.4/8.13.4) with ESMTP id m0GCmLvN006643; Wed, 16 Jan 2008 13:48:21 +0100 (CET) (envelope-from ticso@cicely12.cicely.de) Received: from cicely12.cicely.de (cicely12.cicely.de [10.1.1.14]) by cicely5.cicely.de (8.13.4/8.13.4) with ESMTP id m0GCmDZm080786 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 16 Jan 2008 13:48:13 +0100 (CET) (envelope-from ticso@cicely12.cicely.de) Received: from cicely12.cicely.de (localhost [127.0.0.1]) by cicely12.cicely.de (8.13.4/8.13.3) with ESMTP id m0GCmDM8009084; Wed, 16 Jan 2008 13:48:13 +0100 (CET) (envelope-from ticso@cicely12.cicely.de) Received: (from ticso@localhost) by cicely12.cicely.de (8.13.4/8.13.3/Submit) id m0GCmCrd009083; Wed, 16 Jan 2008 13:48:12 +0100 (CET) (envelope-from ticso) Date: Wed, 16 Jan 2008 13:48:12 +0100 From: Bernd Walter To: Atom Smasher Message-ID: <20080116124812.GR79270@cicely12.cicely.de> References: <20080116094829.55748.qmail@smasher.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080116094829.55748.qmail@smasher.org> X-Operating-System: FreeBSD cicely12.cicely.de 5.4-STABLE alpha User-Agent: Mutt/1.5.9i X-Spam-Status: No, score=-4.4 required=5.0 tests=ALL_TRUSTED=-1.8, BAYES_00=-2.599 autolearn=ham version=3.2.3 X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on cicely12.cicely.de Cc: freebsd-hackers@freebsd.org Subject: Re: disk throughput X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: ticso@cicely.de List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 16 Jan 2008 12:48:24 -0000 On Wed, Jan 16, 2008 at 10:48:27PM +1300, Atom Smasher wrote: > i've got this running in one term: > systat -iostat 1 > and this in another term: > dd if=/dev/acd0 bs=2048 count=123456 | md5 > > apparently the system only knows about throughput of mounted disks? It doesn't seem to know about ata CD drives, SCSI CD drives work fine. Use gstat, which retrieves statistics at a different layer. You should use a multiple of 2k (e.g. 64k) for blocksize though. Just using 2k is likely to be much slower. > is that a bug or a feature? I would say it's a missing feature in acd driver. -- B.Walter http://www.bwct.de http://www.fizon.de bernd@bwct.de info@bwct.de support@fizon.de