From owner-freebsd-usb@FreeBSD.ORG Sat Oct 5 13:35:53 2013 Return-Path: Delivered-To: usb@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 68AA3811 for ; Sat, 5 Oct 2013 13:35:53 +0000 (UTC) (envelope-from jhs@berklix.com) Received: from land.berklix.org (land.berklix.org [144.76.10.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id D33222088 for ; Sat, 5 Oct 2013 13:35:52 +0000 (UTC) Received: from mart.js.berklix.net (p57BCF847.dip0.t-ipconnect.de [87.188.248.71]) (authenticated bits=128) by land.berklix.org (8.14.5/8.14.5) with ESMTP id r95DZinT020385 for ; Sat, 5 Oct 2013 13:35:45 GMT (envelope-from jhs@berklix.com) Received: from fire.js.berklix.net (fire.js.berklix.net [192.168.91.41]) by mart.js.berklix.net (8.14.3/8.14.3) with ESMTP id r95DZU5e019734 for ; Sat, 5 Oct 2013 15:35:30 +0200 (CEST) (envelope-from jhs@berklix.com) Received: from fire.js.berklix.net (localhost.js.berklix.net [127.0.0.1]) by fire.js.berklix.net (8.14.4/8.14.4) with ESMTP id r95DZOx4004869 for ; Sat, 5 Oct 2013 15:35:30 +0200 (CEST) (envelope-from jhs@fire.js.berklix.net) Message-Id: <201310051335.r95DZOx4004869@fire.js.berklix.net> To: usb@freebsd.org Subject: hot usb sticks From: "Julian H. Stacey" Organization: http://berklix.com BSD Linux Unix Consultancy, Munich Germany User-agent: EXMH on FreeBSD http://www.berklix.com/free/ X-URL: http://www.berklix.com/~jhs/cv/ Date: Sat, 05 Oct 2013 15:35:24 +0200 Sender: jhs@berklix.com X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 05 Oct 2013 13:35:53 -0000 Has anyone else noticed how hot USB sticks can get when used for backup ? & also that IO errors occur after a while, which go away after a cold reboot. Not the whole stick, but the metal connector gets hot, so chip is hotter still. Obviously one won't notice this on large plastic encassed sticks, but 2 main sicks I use are: sandisk 2Gig metal case "vendor" "0x0781"; "product" "0x5151"; delock 8G miniature (~ 3mm of platic beyond plug) "vendor" "0x05e3" "product" "0x0727" I usually notice this when I am updating (writing) a crypted (gbde) UFS file systems using port/net/rdist6 (which only rewrites updated files). Source data is 1,446,438 K bytes in 42,611 files so average size of 34 K. But a lot of the files are really small, (~/.* config & mail files etc, so as rdist will be updating each one sequentially, & each will take a read + write cycle on a stick block, & as many small files will probably map to the same stick block, thats some concentrated cycles. More stick detail at http://www.berklix.com/~jhs/src/bsd/fixes/FreeBSD/src/jhs/etc/devd/jhs.conf Quite often I have to reboot my target host that has a stick inserted, I believe regardless of OS version on USB target host Possibly there might be less heating when only reading (as read cycles are also quicker), but mainly I'm backing up, writing. I was thinking of making a heatsink to clamp to a USB socket on an extension cable, but before that I'll try hanging a USB extension cable adjacent to a case fan. Cheers, Julian -- Julian Stacey, BSD Unix Linux C Sys Eng Consultant, Munich http://berklix.com Reply below not above, like a play script. Indent old text with "> ". Send plain text. No quoted-printable, HTML, base64, multipart/alternative.