From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f176.google.com ([209.85.212.176]:35021 "EHLO mail-wi0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750906AbbEJO7B (ORCPT ); Sun, 10 May 2015 10:59:01 -0400 Received: by widdi4 with SMTP id di4so78513169wid.0 for ; Sun, 10 May 2015 07:59:00 -0700 (PDT) Received: from [10.0.2.15] (p4FCB5E8C.dip0.t-ipconnect.de. [79.203.94.140]) by mx.google.com with ESMTPSA id di9sm8813117wib.16.2015.05.10.07.58.58 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 10 May 2015 07:58:59 -0700 (PDT) From: Philip Seeger Message-ID: <554F7232.9080804@googlemail.com> Date: Sun, 10 May 2015 16:58:58 +0200 MIME-Version: 1.0 To: linux-btrfs@vger.kernel.org Subject: Re: Got 10 csum errors according to dmesg but 0 errors according to dev stats References: <554F6D43.2060806@googlemail.com> In-Reply-To: <554F6D43.2060806@googlemail.com> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Forgot to mention kernel version: Linux 4.0.1-1-ARCH $ sudo btrfs fi show Label: none uuid: 3e8973d3-83ce-4d93-8d50-2989c0be256a Total devices 1 FS bytes used 19.87GiB devid 1 size 45.00GiB used 21.03GiB path /dev/sda1 btrfs-progs v3.19.1 On 05/10/2015 04:37 PM, Philip Seeger wrote: > I have installed a new virtual machine (VirtualBox) with Arch on btrfs > (just a root fs and swap partition, no other partitions). > I suddenly noticed 10 checksum errors in the kernel log: > $ dmesg | grep csum > [ 736.283506] BTRFS warning (device sda1): csum failed ino 1704363 off > 761856 csum 1145980813 expected csum 2566472073 > [ 736.283605] BTRFS warning (device sda1): csum failed ino 1704363 off > 1146880 csum 1961240434 expected csum 2566472073 > [ 745.583064] BTRFS warning (device sda1): csum failed ino 1704346 off > 393216 csum 4035064017 expected csum 2566472073 > [ 752.324899] BTRFS warning (device sda1): csum failed ino 1705927 off > 2125824 csum 3638986839 expected csum 2566472073 > [ 752.333115] BTRFS warning (device sda1): csum failed ino 1705927 off > 2588672 csum 176788087 expected csum 2566472073 > [ 752.333303] BTRFS warning (device sda1): csum failed ino 1705927 off > 3276800 csum 1891435134 expected csum 2566472073 > [ 752.333397] BTRFS warning (device sda1): csum failed ino 1705927 off > 3964928 csum 3304112727 expected csum 2566472073 > [ 2761.889460] BTRFS warning (device sda1): csum failed ino 1705927 off > 2125824 csum 3638986839 expected csum 2566472073 > [ 9054.226022] BTRFS warning (device sda1): csum failed ino 1704363 off > 761856 csum 1145980813 expected csum 2566472073 > [ 9054.226106] BTRFS warning (device sda1): csum failed ino 1704363 off > 1146880 csum 1961240434 expected csum 2566472073 > > This is a new vm, it hasn't crashed (which might have caused filesystem > corruption). The virtual disk is on a RAID storage on the host, which is > healthy. All corrupted files are Firefox data files: > $ dmesg | grep csum | grep -Eo 'csum failed ino [0-9]* ' | awk '{print > $4}' | xargs -I{} find -inum {} > ./.mozilla/firefox/nfh217zw.default/cookies.sqlite > ./.mozilla/firefox/nfh217zw.default/cookies.sqlite > ./.mozilla/firefox/nfh217zw.default/webappsstore.sqlite > ./.mozilla/firefox/nfh217zw.default/places.sqlite > ./.mozilla/firefox/nfh217zw.default/places.sqlite > ./.mozilla/firefox/nfh217zw.default/places.sqlite > ./.mozilla/firefox/nfh217zw.default/places.sqlite > ./.mozilla/firefox/nfh217zw.default/places.sqlite > ./.mozilla/firefox/nfh217zw.default/cookies.sqlite > ./.mozilla/firefox/nfh217zw.default/cookies.sqlite > > How could this possibly happen? > > And more importantly: Why doesn't the btrfs stat(u)s output tell me that > errors have occurred? > $ sudo btrfs dev stats / > [/dev/sda1].write_io_errs 0 > [/dev/sda1].read_io_errs 0 > [/dev/sda1].flush_io_errs 0 > [/dev/sda1].corruption_errs 0 > [/dev/sda1].generation_errs 0 > > If the filesystem health was monitored using btrfs dev stats (cronjob) > (like checking a zpool using zpool status), the admin would not have > been notified: > $ sudo btrfs dev stats / | grep -v 0 -c > 0 > > Is my understanding of the stats command wrong, does "corruption_errs" > not mean corruption errors? > > > -- Philip