From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264087AbTICRT1 (ORCPT ); Wed, 3 Sep 2003 13:19:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264125AbTICRSg (ORCPT ); Wed, 3 Sep 2003 13:18:36 -0400 Received: from pc1-cwma1-5-cust4.swan.cable.ntl.com ([80.5.120.4]:48844 "EHLO dhcp23.swansea.linux.org.uk") by vger.kernel.org with ESMTP id S264115AbTICRRZ (ORCPT ); Wed, 3 Sep 2003 13:17:25 -0400 Subject: Re: Kernel 2.4: Load average scaling to 200! From: Alan Cox To: James Vanns Cc: Linux Kernel Mailing List In-Reply-To: <1062605821.23773.15.camel@eeyore.ntnet.cc.local> References: <1062605821.23773.15.camel@eeyore.ntnet.cc.local> Content-Type: text/plain Content-Transfer-Encoding: 7bit Message-Id: <1062609387.19058.138.camel@dhcp23.swansea.linux.org.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.4 (1.4.4-4) Date: Wed, 03 Sep 2003 18:16:28 +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mer, 2003-09-03 at 17:17, James Vanns wrote: > When using mt on RedHat Linux 8 running kernel 2.4.20 to fsf on an LTO > tape drive the load average soars to 100+ and denies everyone the mail > service it's used for (IMAP). I have to reboot the server as I cannot > kill mt. I can think of two possible causes here. #1 is that something hung the scsi bus because of a crash - be it kernel, mt, hardware whatever. The other one some people hit with tape drives is that they don't have disconnect enabled on the drive (check your drive manuals). With disconnect disabled the tape will hog the bus for the entire time it is doing a command. The tapes I have don't seem to take long enough to fsf (even if they are past the last marker) to worry too much however. Do you also get messages about scsi timeouts What card ?