From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754874AbZJDKuA (ORCPT ); Sun, 4 Oct 2009 06:50:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753674AbZJDKt7 (ORCPT ); Sun, 4 Oct 2009 06:49:59 -0400 Received: from mail-gx0-f212.google.com ([209.85.217.212]:62329 "EHLO mail-gx0-f212.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752580AbZJDKt6 (ORCPT ); Sun, 4 Oct 2009 06:49:58 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=N7oBTPGdbHmTDIdk4N0Zg4xagnO7JrbIIh8Xy5Q7FoKDWgTCjjnt9OOznjAX9ejAi8 omQZBbeU0f2ue1uDd2xUsSd3CS3KG+qpcyjUN6TgRelDzqmjvxZNng9Ak7hEA+ksp7VF fGBeDZ3D20Y1dGFmAcIvi/kN6drTvko5/Rk/Q= MIME-Version: 1.0 Date: Sun, 4 Oct 2009 12:49:19 +0200 Message-ID: <4e5e476b0910040349l21b69a97o7a11b2138bc8f573@mail.gmail.com> Subject: [bisected] commit: a9327cac440be4d8333bba975cbbf76045096275 causes iostat output From: Corrado Zoccolo To: Linux-Kernel , knikanth@suse.de, jens.axboe@oracle.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, with 2.6.32-rc1 I started getting the following strange output from "iostat -kx 2": Linux 2.6.31bisect (et2) 04/10/2009 _i686_ (2 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 10,70 0,00 3,16 15,75 0,00 70,38 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 18,22 0,00 0,67 0,01 14,77 0,02 43,94 0,01 10,53 39043915,03 2629219,87 sdb 60,89 9,68 50,79 3,04 1724,43 50,52 65,95 0,70 13,06 488437,47 2629219,87 avg-cpu: %user %nice %system %iowait %steal %idle 2,72 0,00 0,74 0,00 0,00 96,53 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 sdb 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 avg-cpu: %user %nice %system %iowait %steal %idle 6,68 0,00 0,99 0,00 0,00 92,33 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 sdb 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 avg-cpu: %user %nice %system %iowait %steal %idle 4,40 0,00 0,73 1,47 0,00 93,40 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 sdb 0,00 4,00 0,00 3,00 0,00 28,00 18,67 0,06 19,50 333,33 100,00 Global values for service time and utilization are garbage. For interval values, utilization is always 100%, and service time is higher than normal. I bisected it down to: [a9327cac440be4d8333bba975cbbf76045096275] Seperate read and write statistics of in_flight requests and verified that reverting just that commit indeed solves the issue on 2.6.32-rc1. My sysstat package is: [corrado@et2 linux-2.6]$ rpm -qi sysstat Name : sysstat Relocations: (not relocatable) Version : 9.0.1 Vendor: Mandriva Release : 1mdv2009.1 Build Date: mer 11 mar 2009 20:50:16 CET Install Date: lun 27 lug 2009 21:25:13 CEST Build Host: n2.mandriva.com Group : System/Configuration/Other Source RPM: sysstat-9.0.1-1mdv2009.1.src.rpm Size : 681881 License: GPL Signature : DSA/SHA1, gio 23 apr 2009 20:40:00 CEST, Key ID 445935f878d019f5 Packager : Frederik Himpe URL : http://perso.wanadoo.fr/sebastien.godard Summary : Includes the sar and iostat system monitoring commands Description : This package provides the sar and iostat commands for the Linux operating system, similar to their traditional UNIX counterparts. They enable system monitoring of disk, network, and other IO activity. Thanks, Corrado -- __________________________________________________________________________ dott. Corrado Zoccolo mailto:czoccolo@gmail.com PhD - Department of Computer Science - University of Pisa, Italy --------------------------------------------------------------------------