From owner-freebsd-usb@FreeBSD.ORG Mon Oct 26 10:24:06 2009 Return-Path: Delivered-To: freebsd-usb@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5B21D106566B; Mon, 26 Oct 2009 10:24:06 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id 187E58FC0C; Mon, 26 Oct 2009 10:24:06 +0000 (UTC) Received: from [10.0.0.198] (198.imp.bsdimp.com [10.0.0.198] (may be forged)) by harmony.bsdimp.com (8.14.3/8.14.1) with ESMTP id n9QAKfnt072691; Mon, 26 Oct 2009 04:20:41 -0600 (MDT) (envelope-from imp@bsdimp.com) From: Warner Losh To: Hans Petter Selasky In-Reply-To: <200910260959.20772.hselasky@c2i.net> X-Mailer: iPhone Mail (7D11) References: <20091025.133437.-1844000782.imp@bsdimp.com> <4AE4E7AF.8060103@ever.sanda.gr.jp> <200910260959.20772.hselasky@c2i.net> Message-Id: <96830A33-8392-4C05-B073-48026E24C895@bsdimp.com> Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (iPhone Mail 7D11) Date: Mon, 26 Oct 2009 04:20:38 -0600 Cc: "hackers@FreeBSD.org" , "non@ever.sanda.gr.jp" , "freebsd-usb@FreeBSD.org" Subject: Re: Help troubleshooting... X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 Oct 2009 10:24:06 -0000 But there was no indication the device went missing on the console. And it wasn't until I unplugged it that da0 detached. Usually in the past when it has started throwing errors the console was chatty about why. Warner On Oct 26, 2009, at 2:59 AM, Hans Petter Selasky wrote: > On Monday 26 October 2009 01:05:03 non@ever.sanda.gr.jp wrote: >> M. Warner Losh wrote: >>> I have a usb stick (8GB) on it. This stick has about 5GB of junk on >>> it at this point. >>> >>> I tried to do 'cat * > /dev/null' recently, to measure how fast it >>> goes. It got about 1GB into the drive and then I got device missing >>> messages. >>> >>> So devfs thinks the device went missing: >> >> Warner-san, maybe it is caused by the hardware problem on the USB >> flash >> memory. Some chip on the memory might have too much heat when you >> access >> the memory at fast rate. Then it stops working. >> > > What happens if you read from two USB disks at the same time? > > If the device went missing the USB HUB signalled that. This is maybe > an > indication that the USB firmware on the device crashed. Maybe this > is due to > heat, or unhandled race conditions when the load goes high. > > Try using "dd" and vary the block size from 512 to 65536 bytes. Does > it stop > working with all block sizes over time? > > --HPS > >