From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takahiro Yasui Date: Thu, 06 May 2010 19:42:47 -0400 Subject: [RFC PATCH] Reduce noise about missing devices. In-Reply-To: <20100505190119.GF27027@agk-dp.fab.redhat.com> References: <87k4rsa8fd.fsf@twilight.int.mornfall.net.> <20100505190119.GF27027@agk-dp.fab.redhat.com> Message-ID: <4BE353F7.3040305@redhat.com> List-Id: To: lvm-devel@redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On 05/05/10 15:01, Alasdair G Kergon wrote: > On Tue, Apr 27, 2010 at 11:32:06PM +0200, Peter Rockai wrote: >> this is not intended to be directly applied, but more to start a >> discussion. One problem with our handling of missing devices is the huge >> amount of log noise each missing device produces. In a single run of >> lvconvert --repair, I get multiple screens of "read error" and "Couldn't >> find device with uuid"... > > Well my first question before suppressing messages would be: Are all the > repeated accesses that generate the messages actually necessary? > Or are the messages just a symptom of other problems which should be > addressed instead? I checked how many times a broken device was accessed by the lvconvert command when 'lvconvert --repair' is executed using the following lvm environment: VG: 3PVs LV: mirror composed of 2 legs and 1 disk log vg00-lv00 (253:3) |-vg00-lv00_mimage_1 (253:2) | `- (8:48) |-vg00-lv00_mimage_0 (253:1) | `- (8:32) `-vg00-lv00_mlog (253:0) `- (8:64) When a primary leg is broken, 'lvconvert --repair' accesses the primary leg by '47 times.' I think what we should do is to suppress 'access to a broken device' instead of suppressing 'displaying error messages.' Suppress error messages might be friendly to some users, but other users might not notice how often a broken device is accessed by the lvconvert command. Do we need to access a broken device so many times? If lvm commands detects errors on a device a few times, my opinion is that lvm commands should quit accessing the device. Thanks, Taka