From owner-freebsd-usb@FreeBSD.ORG Mon Oct 26 11:53:06 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 E9BE6106566C; Mon, 26 Oct 2009 11:53:06 +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 A9DB78FC16; Mon, 26 Oct 2009 11:53:06 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by harmony.bsdimp.com (8.14.3/8.14.1) with ESMTP id n9QBm5BM073716; Mon, 26 Oct 2009 05:48:06 -0600 (MDT) (envelope-from imp@bsdimp.com) Date: Mon, 26 Oct 2009 05:48:16 -0600 (MDT) Message-Id: <20091026.054816.1631944692.imp@bsdimp.com> To: hselasky@c2i.net From: "M. Warner Losh" In-Reply-To: <200910260959.20772.hselasky@c2i.net> References: <20091025.133437.-1844000782.imp@bsdimp.com> <4AE4E7AF.8060103@ever.sanda.gr.jp> <200910260959.20772.hselasky@c2i.net> X-Mailer: Mew version 5.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit 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 11:53:07 -0000 In message: <200910260959.20772.hselasky@c2i.net> Hans Petter Selasky writes: : 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? I know that the august 25th version failed badly when I tried to burn DVDs from a USB drive to a USB attached DVD burner. This used to work flawlessly. : 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. This same flash drive will do 20MB sustained on windows without a glitch using similar commands. : Try using "dd" and vary the block size from 512 to 65536 bytes. Does it stop : working with all block sizes over time? Once I get the message I posted, it is lights out for da0. No further access to the drive works at all. Warner