From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 5 Dec 2001 22:02:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 5 Dec 2001 22:02:01 -0500 Received: from mplspop4.mpls.uswest.net ([204.147.80.14]:10763 "HELO mplspop4.mpls.uswest.net") by vger.kernel.org with SMTP id ; Wed, 5 Dec 2001 22:01:56 -0500 Date: Wed, 5 Dec 2001 21:01:54 -0600 Message-ID: <20011206030154.GA5979@iucha.net> From: "Florin Iucha" To: linux-kernel@vger.kernel.org Cc: faith@acm.org Subject: Adaptec-2920 eats too much cpu time when reading from the CD-ROM Mail-Followup-To: linux-kernel@vger.kernel.org, faith@acm.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.24i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, I have recently purchased a Plextor 12x CD-RW and I have attached it to and Adaptec-2920 SCSI card. The card uses the "Future Domain Corp. TMC-18C30 [36C70]" chip. The problem I see: when reading from the CD-RW my system becomes very unresponsive and top reveals 90-95% of the time is spent on "system". My CPU is AMD K6-III/500MHz with 256 Mb RAM. When reading the same CD using the IDE DVD-ROM the time spent in system is 5%. Also when the CD-RW is connected to the Advansys SCSI controller the CPU usage is also negligible. The Adaptec-2920 uses IRQ 10 and does not share it with any other board. I notice an unusual number of interrupts in /proc/interrupts: after the machine has been up for a couple of hours and I have written three CDs, the statistics are: CPU0 0: 638458 XT-PIC timer 1: 15325 XT-PIC keyboard 2: 0 XT-PIC cascade 5: 0 XT-PIC es1371 8: 1 XT-PIC rtc 9: 17004 XT-PIC usb-uhci 10: 3032143 XT-PIC fdomain 11: 58021 XT-PIC advansys 12: 2995779 XT-PIC eth0 14: 107542 XT-PIC ide0 15: 6895 XT-PIC ide1 When loading the fdomain module I get: scsi1: No BIOS; using scsi id 7 scsi1: TMC-36C70 (PCI bus) chip at 0xdc00 irq 10 Bad boy: fdomain (at 0xd08b7866) called us without a dev_id! Is there anything I can try? Thanks, florin -- "If it's not broken, let's fix it till it is." 41A9 2BDE 8E11 F1C5 87A6 03EE 34B3 E075 3B90 DFE4