From owner-freebsd-current@FreeBSD.ORG Wed May 7 15:34:30 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 14E3A37B401 for ; Wed, 7 May 2003 15:34:29 -0700 (PDT) Received: from alpha.siliconlandmark.com (alpha.siliconlandmark.com [209.69.98.4]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9B64D43F3F for ; Wed, 7 May 2003 15:34:28 -0700 (PDT) (envelope-from andy@siliconlandmark.com) Received: from alpha.siliconlandmark.com (localhost [127.0.0.1]) h47MYRHE002670 for ; Wed, 7 May 2003 18:34:27 -0400 (EDT) (envelope-from andy@siliconlandmark.com) Received: from localhost (andy@localhost)h47MYRpT002667 for ; Wed, 7 May 2003 18:34:27 -0400 (EDT) (envelope-from andy@siliconlandmark.com) X-Authentication-Warning: alpha.siliconlandmark.com: andy owned process doing -bs Date: Wed, 7 May 2003 18:34:27 -0400 (EDT) From: Andre Guibert de Bruet To: current@freebsd.org Message-ID: <20030507181628.J30571@alpha.siliconlandmark.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: High CPU utilization even with DMA enabled? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 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: Wed, 07 May 2003 22:34:30 -0000 Hi, Here's the output of top while moving a large file from one disk to another on my otherwise idle desktop machine: PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU COMMAND 26 root -68 -187 0K 12K WAIT 0 141:36 79.98% 79.98% irq7: dc0 ohci0 11 root -16 20 0K 12K RUN 1 13:45 34.86% 34.86% idle: cpu1 12 root -16 20 0K 12K CPU0 0 13:46 30.32% 30.32% idle: cpu0 21069 root 116 0 608K 136K RUN 1 0:58 16.41% 16.41% mv 647 dnetc 128 20 1032K 656K RUN 0 826:51 9.28% 9.28% dnetc 656 dnetc 128 20 1016K 556K RUN 0 829:36 8.15% 8.15% dnetc 14 root -48 -167 0K 12K WAIT 0 9:27 4.88% 4.88% swi7: tty:sio clock 3 root -8 0 0K 12K g_up 0 4:06 2.88% 2.88% g_up 24 root -64 -183 0K 12K WAIT 0 0:27 1.22% 1.22% irq15: ata1 This system has the following IDE configuration: ATA channel 0: Master: no device present Slave: acd0 ATA/ATAPI rev 0 ATA channel 1: Master: ad2 ATA/ATAPI rev 6 Slave: no device present ATA channel 2: Master: ad4 ATA/ATAPI rev 7 Slave: no device present ATA channel 3: Master: ad6 ATA/ATAPI rev 7 Slave: no device present The files I'm moving are several gigabytes large and they're going from ad6 to ad2. The motherboard is an Asus A7M266D, with onboard ATA100 channels (0,1) and a Promise Tech ATA133 card installed (channels 2,3). Now, I realize that copying a file from one disk to another requires cpu cycles even with DMA enabled, but is 80% of cpu usage to be expected? Also, wouldn't one expect process id 24 (irq15: ata1) to be using CPU during such transfers? Regards, PS: dmesg, pciconf -vl and other information is available, if needed. > Andre Guibert de Bruet | Enterprise Software Consultant > > Silicon Landmark, LLC. | http://siliconlandmark.com/ >