From owner-freebsd-current@FreeBSD.ORG Tue Dec 12 12:47:59 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 8A9F516A583 for ; Tue, 12 Dec 2006 12:47:59 +0000 (UTC) (envelope-from jhs@flat.berklix.net) Received: from thin.berklix.org (thin.berklix.org [194.246.123.68]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8365543CC3 for ; Tue, 12 Dec 2006 12:46:36 +0000 (GMT) (envelope-from jhs@flat.berklix.net) Received: from js.berklix.net (p549A7155.dip.t-dialin.net [84.154.113.85]) (authenticated bits=128) by thin.berklix.org (8.12.11/8.12.11) with ESMTP id kBCClu2X051452; Tue, 12 Dec 2006 13:47:56 +0100 (CET) (envelope-from jhs@flat.berklix.net) Received: from fire.jhs.private (fire.jhs.private [192.168.91.41]) by js.berklix.net (8.13.6/8.13.6) with ESMTP id kBCClnDh006541; Tue, 12 Dec 2006 13:47:50 +0100 (CET) (envelope-from jhs@flat.berklix.net) Received: from fire.jhs.private (localhost [127.0.0.1]) by fire.jhs.private (8.13.6/8.13.6) with ESMTP id kBCClnAG002515; Tue, 12 Dec 2006 13:47:49 +0100 (CET) (envelope-from jhs@fire.jhs.private) Message-Id: <200612121247.kBCClnAG002515@fire.jhs.private> To: "Pascal Hofstee" In-reply-to: References: Comments: In-reply-to "Pascal Hofstee" message dated "Tue, 12 Dec 2006 11:54:40 +0100." Date: Tue, 12 Dec 2006 13:47:49 +0100 From: "Julian H. Stacey" Cc: FreeBSD Current Subject: Re: umass intermittently "stalling" ... processes seemingly stuck in "wdrain" state 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: Tue, 12 Dec 2006 12:47:59 -0000 "Pascal Hofstee" wrote: > I recently bought an USB Mass Storage unit (about 300GB) and a 4+1 > slot PCI USB2.0 card (since it's an old box that didn't have USB 2 on > board yet), and i have noticed that intermittently the device "stalls" > any operations that try to access it: > > - copying data onto the disk > - reading data from the disk > - running an ls while inside a directory on the disk's mount point > > Today while trying to scp a fairly large set of files from my office > system to my umass disk at home i noticed the similar stalling > behaviour and decided to check ps output on my home system. There i > noticed that every single time to scp session would begin stalling > (lasting up to about 30-40s per stall) ... the scp process on my > home-system would have dropped into a wdrain state. > > As soon as the scp process (after about 30 or more seconds) would > finally get out of this wdrain state (usually into an sbwait state) > the scp process on my work system would start picking up transfer > speed again until the next slip into wdrain. > > I haven't been able to test this on a non-CURRENT system yet so i am > not sure wether or not this is a CURRENT only issue or a more generic > problem, but if somebody could give some pointers on where to start > looking on fixing this ... i am open for suggestions. I've seen stalling on 1 of 2 x 6.1-RELEASE hosts. I was given an 80 Gig external USB (Freecom) (disc reported to be unstable on XP, but as I don't run XP ... :-). I ran disc for a long time OK via a Zediworks USB2 powered hub, to a Belkin USB2 Cardbus on my laptop with 6.1-RELEASE. No recent problems (OK, various USB2 devices on laptop used to cause crashes, (that didnt crash on the inbuilt USB-1), I assumed it was because Belkin overheating - card got too hot to touch in middle ! (My brother reckons his Belkin may have died in my laptop under FreeBSD, his identical laptop didnt kill his Belkin under XP - my guess was maybe FreeBSD wasn't switching Belkin card into idle state to keep it cool ? but that's another issue)). Moved 80G drive to a direct connection on main 6.1-RELEASE tower. Persistent hangs. umount -f would eventually work, then I did fsck & mount, & repeated. I didnt observe ps states. Moved disc back to laptop, no hangs. I'd assumed hardware problem & thought next to try moving hub too. Now I've read your post I'll look at PS states too. (My 80G drive is a 3.5" with own power supply, not a laptop drive in external unpowered box needing more than the 0.5A delivered by a USB connection.) -- Julian Stacey. BSD Unix C Net Consultancy, Munich/Muenchen http://berklix.com Mail Ascii, not HTML. Ihr Rauch = mein allergischer Kopfschmerz. http://berklix.org/free-software