From owner-freebsd-current@FreeBSD.ORG Sun Mar 9 20:42:15 2008 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 3280F106566B for ; Sun, 9 Mar 2008 20:42:15 +0000 (UTC) (envelope-from duncan.young@pobox.com) Received: from out4.smtp.messagingengine.com (out4.smtp.messagingengine.com [66.111.4.28]) by mx1.freebsd.org (Postfix) with ESMTP id F1AEF8FC1F for ; Sun, 9 Mar 2008 20:42:14 +0000 (UTC) (envelope-from duncan.young@pobox.com) Received: from compute1.internal (compute1.internal [10.202.2.41]) by out1.messagingengine.com (Postfix) with ESMTP id 61728BF1F0; Sun, 9 Mar 2008 16:42:14 -0400 (EDT) Received: from heartbeat2.messagingengine.com ([10.202.2.161]) by compute1.internal (MEProxy); Sun, 09 Mar 2008 16:42:14 -0400 X-Sasl-enc: Io+wEAxIU+gNQ3Cgsrf7nBvka4vPX+JYFji8uMNA/N+M 1205095333 Received: from triple0.qld.optushome.com.au (c210-49-75-149.rochd2.qld.optusnet.com.au [210.49.75.149]) by mail.messagingengine.com (Postfix) with ESMTPSA id E2F6531FB1; Sun, 9 Mar 2008 16:42:13 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by triple0.qld.optushome.com.au (Postfix) with ESMTP id B86B36DFA; Mon, 10 Mar 2008 06:42:10 +1000 (EST) From: Duncan Young To: Ben Stuyts Date: Mon, 10 Mar 2008 06:42:09 +1000 User-Agent: KMail/1.9.7 References: <200803091525.27311.duncan.young@pobox.com> <990680CB-A797-41C2-BDF0-E4968DFBDB94@altesco.nl> In-Reply-To: <990680CB-A797-41C2-BDF0-E4968DFBDB94@altesco.nl> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200803100642.09864.duncan.young@pobox.com> Cc: freebsd-current@freebsd.org Subject: Re: write cache on usb disks and zfs X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: duncan.young@pobox.com List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 09 Mar 2008 20:42:15 -0000 Thanks for the reply. This was exactly what I was after, many thanks. Once I've sorted through my various usb caddies, I'll submit a similar PR. regards Duncan On Sun, 9 Mar 2008 10:45:22 pm Ben Stuyts wrote: > Hi, > > On 9 Mar 2008, at 06:25, Duncan Young wrote: > > I am trying to use the USB drives for backup and would like to use > > zfs on > > them, but the problem I have is with the cache disabled, I get lots of > > > > kernel: (da2:umass-sim0:0:0:0): SYNCHRONIZE CACHE. CDB: 35 0 0 0 0 0 > > 0 0 0 0 > > kernel: (da2:umass-sim0:0:0:0): CAM Status: SCSI Status Error > > kernel: (da2:umass-sim0:0:0:0): SCSI Status: Check Condition > > kernel: (da2:umass-sim0:0:0:0): ILLEGAL REQUEST asc:20,0 > > kernel: (da2:umass-sim0:0:0:0): Invalid command operation code > > kernel: (da2:umass-sim0:0:0:0): Unretryable error > > > > errors in /var/log/messages. > > > > I am assuming that the error messages are harmless, but it would be > > nice for > > zfs to pay attention and not continually issue the commands. Is > > there a way > > to do this? > > I had exactly the same problem (on 7-stable) and have added a quirk > for this particular drive to scsi_da.c. In my case the drive became > unresponsive for a few seconds, so the transfer rate was very low. > > Works fine so far with the quirk. I have filed a PR where you can see > my changes: http://www.freebsd.org/cgi/query-pr.cgi?pr=121474 > > Ben