From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Kuzminsky Subject: strange data from iostat (2.6.16.24) Date: Mon, 10 Jul 2006 13:08:49 -0600 Message-ID: Return-path: Received: from rwcrmhc15.comcast.net ([216.148.227.155]:38895 "EHLO rwcrmhc15.comcast.net") by vger.kernel.org with ESMTP id S1422790AbWGJTVE (ORCPT ); Mon, 10 Jul 2006 15:21:04 -0400 Received: from seb (helo=highlab.com) by highlab.com with local-esmtp (Exim 4.62) (envelope-from ) id 1G017h-00075R-2X for linux-ide@vger.kernel.org; Mon, 10 Jul 2006 13:08:49 -0600 Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: linux-ide@vger.kernel.org I've got a system with 4 SATA disks hanging off an ICH6 controller, and I'm seeing output from iostat that I dont understand: 0 seb@slurp /home/seb> iostat -dkx 1 Linux 2.6.16.24-slurp (slurp) 07/10/06 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util hda 0.01 0.04 0.18 0.02 0.74 0.26 9.69 0.05 236.03 7.61 0.16 hdb 0.03 2.67 0.89 0.57 6.87 13.01 27.08 0.03 19.34 2.39 0.35 sda 0.04 0.11 0.46 0.14 1.99 1.03 10.00 95.31 22.04 1657.68 99.96 sdb 0.04 0.11 0.30 0.13 1.37 0.95 10.79 95.31 34.64 2326.63 99.96 sdc 0.05 0.10 0.29 0.14 1.34 0.98 10.83 95.31 36.00 2334.50 99.96 sdd 0.05 0.10 0.28 0.14 1.32 0.95 10.95 95.31 33.63 2407.25 99.96 md0 0.00 0.00 1.12 0.46 4.49 1.83 8.00 0.00 0.00 0.00 0.00 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util hda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 hdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251470.59 0.00 0.00 99.01 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251470.59 0.00 0.00 99.01 sdc 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251470.59 0.00 0.00 99.01 sdd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251470.59 0.00 0.00 99.01 md0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util hda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 hdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4293981.37 0.00 0.00 100.40 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4293981.37 0.00 0.00 100.40 sdc 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4293981.37 0.00 0.00 100.40 sdd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4293981.37 0.00 0.00 100.40 md0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util hda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 hdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251466.70 0.00 0.00 99.41 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251466.70 0.00 0.00 99.41 sdc 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251466.70 0.00 0.00 99.41 sdd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4251466.70 0.00 0.00 99.41 md0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 md0 is a raid5 of sd[abcd]. The system is pretty much idle, so the queue size and device utilization make no sense to me. The system seems fine and stable, just the iostats are surprising. Any ideas here? -- Sebastian Kuzminsky If it isn't running programs and it isn't fusing atoms, it's just bending space. -- Ken MacLeod