From owner-freebsd-current@FreeBSD.ORG Wed Apr 6 17:47:58 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 03A991065782 for ; Wed, 6 Apr 2011 17:47:58 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-ww0-f50.google.com (mail-ww0-f50.google.com [74.125.82.50]) by mx1.freebsd.org (Postfix) with ESMTP id 87AB28FC1C for ; Wed, 6 Apr 2011 17:47:56 +0000 (UTC) Received: by wwc33 with SMTP id 33so2019945wwc.31 for ; Wed, 06 Apr 2011 10:47:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:message-id:date:from:user-agent :mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=WWwCSa0YwHI7IDGQWVyJhK3CnZc7dkFaU0wuiiOQngk=; b=VR4dC+e/d95KrHL1ul6oGlkBKVwCDjpzjuTybpbdw4QtFNfynZE1sgtE6/2OEXogyF rc3jeLpy3LJ+xa9koxY2NaTRY+mWd9AZvS/kd/OAanbkgw42sBmFohocT4siQSvACkSP hkN1NrcdC8U4BzsTtRhdqhnk+kvXFSTcX9hjc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=XKUIBL5H+c4gdlJ2bPhq2FyLmdpRzu9jJzTkMoK78sPQs3x/Sc/ekG9zwT7TjdGroG 028P6W7j7GlvpEEH6X85MaxpAGv7SI0LpDkFcoDMXVbxdhwnZ9hxu2QPzXE/hlsPs+YZ F0FtVGMspbpiwwSVV1mnFA3VH+OciBCtP6AuQ= Received: by 10.216.241.4 with SMTP id f4mr1382879wer.42.1302112076053; Wed, 06 Apr 2011 10:47:56 -0700 (PDT) Received: from mavbook2.mavhome.dp.ua (pc.mavhome.dp.ua [212.86.226.226]) by mx.google.com with ESMTPS id k76sm415769wej.19.2011.04.06.10.47.54 (version=SSLv3 cipher=OTHER); Wed, 06 Apr 2011 10:47:55 -0700 (PDT) Sender: Alexander Motin Message-ID: <4D9CA746.6000606@FreeBSD.org> Date: Wed, 06 Apr 2011 20:47:50 +0300 From: Alexander Motin User-Agent: Thunderbird 2.0.0.23 (X11/20091212) MIME-Version: 1.0 To: John Baldwin References: <20110331223339.GA13682@freebsd.org> <201104010843.47367.jhb@freebsd.org> <20110404204316.GA11367@freebsd.org> <201104041719.33844.jhb@freebsd.org> In-Reply-To: <201104041719.33844.jhb@freebsd.org> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Alexander Best , freebsd-current@freebsd.org Subject: Re: multiple issues with devstat_*(9) 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: Wed, 06 Apr 2011 17:47:58 -0000 John Baldwin wrote: > On Monday, April 04, 2011 4:43:16 pm Alexander Best wrote: >> On Fri Apr 1 11, John Baldwin wrote: >>> This is probably due to the hard drives being IDE (really ATA) rather than >>> SCSI. I agree this should show the pass devices. >> hmmmm...one could argue. the drives are ATA, however they are being associated >> to the CAM subsystem. depends what one considers under "scsi interface". >> personally i'd like to see them inder "scsi". > > No, SCSI is a transport protocol. Alexandar Motin's work added a new > transport layer that speaks ATA and that is what ada uses. CAM does not > send SCSI commands to adaX devices AFAIK. Generally right, but to be complete: CAM differentiates types at transport and protocol layers. At the protocol layer there are SCSI and ATA protocols (used by da and ada drivers respectively, for example). At the transport layer there never was such thing as "SCSI", there are: SPI, FC, SAS, PPB, USB (several protocols), iSCSI, etc. All of them can handle SCSI commands. Newly added ATA and SATA transports handle both ATA and SCSI commands: ATA -- always, SCSI -- optionally, using ATAPI extension. >>>> otaku% iostat -t ide >>>> tty cpu >>>> tin tout us ni sy in id >>>> 1 92 5 0 4 0 90 >>>> otaku% iostat -t other >>>> tty cpu >>>> tin tout us ni sy in id >>>> 1 92 5 0 4 0 90 >>>> >>>> ...what about md0? ada0? ada1? md0? >>> md0 is a memory disk, it is neither SCSI nor IDE. However, -t ide (or even >>> better, a -t ata), should show all of your other devices (adaX and cd0) along >>> with their passX devices I think. >> so md0 should show up under -t other. i don't think there's a -t ata. > > Yes, I think we should possibly add a -t ata, possibly as an alias for > -t ide. Have no objections, but I would like to clarify what exactly that option should mean. It is simple for cases of SATA and SAS disks -- first is IDE/ATA (ATA/SATA), second is SCSI (SCSI/SAS). But it becomes tricky for ATA/SATA CD/DVD, ZIP/MO, tape drives - they use SCSI protocol commands, but ATA/SATA transport. As result, while adaX devices are definitely IDE (ATA) from any point of view; cdX, daX, saX, etc. can use any transport. So should they be reported as SCSI, respecting command protocol, or IDE (ATA), respecting transport? -- Alexander Motin