From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f178.google.com ([209.85.212.178]:34957 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757711AbbIVOnP convert rfc822-to-8bit (ORCPT ); Tue, 22 Sep 2015 10:43:15 -0400 Received: by wicge5 with SMTP id ge5so164859346wic.0 for ; Tue, 22 Sep 2015 07:43:14 -0700 (PDT) Date: Tue, 22 Sep 2015 16:43:12 +0200 From: "S. Fricke" To: Richard Michael Cc: Holger =?iso-8859-1?Q?Hoffst=E4tte?= , Linux Btrfs Subject: Re: problem with long running btrfs mount operation Message-ID: <20150922144312.GB14395@sfserver> References: <20150922133813.GA14395@sfserver> <56015D3F.8020406@googlemail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, > On Tue, Sep 22, 2015 at 9:53 AM, Holger Hoffstätte > wrote: > > On 09/22/15 15:38, S. Fricke wrote: > >> I have a problem with one of my btrfs hdds. If I mount it, it needs more than > >> 135 minutes for this operation. After the mounting it works normaly. This is > >> reproducible only with this hdd. > >> > >> Maybe someone has a clue what is going wrong here. > > > > On remount it tries to continue a previously started balance, which fails with > > an error (as can be seen at the end of your log). You should: > > > > a) immediately stop what you're doing on that fs and unmount it > > b) get btrfs-progs-4.2.1 (not 4.2) and see what it says What should it say to me? I have to send a command? Should I try to mount the device after I have unmount it? BTW: Is btrfs-progs needed for mounting? > > > > Depending on the outcome of b) you can use -o skip_balance on the next mount. > > > > -h > > I'm curious, do the relevant INFO lines also appear earlier in the > log, near the time the mount began? > > These: > > BTRFS: checking UUID tree > [ +0.000076] BTRFS info (device sda1): continuing balance > > > Otherwise, it requires an unknown amount of patience to diagnose this > problem -- how long should I wait before giving up? > > It seems to me, from a sysadmin's perspective, the log messages are > reversed (hung task, 2+ hrs later, BTRFS tells me what it's doing) . > I'd expect BTRFS to log a "continuing balance" message as soon as I > mount it, then it's blocked [for as long as I care to wait], but I can > immediately tell what's happened. Thats my problem in general with btrfs, and other filesystems, I have a glitch; I have to wait, but I have no possibilities to look what is going on on drive X. Okay I could use sysemtaps, has someone good scripts for such usecase? Or maybe we have other toolings? Regards, Silvio -- -- S. Fricke ---------------------------------------- silvio@port1024.net -- Diplom-Informatiker (FH) Linux-Entwicklung JABBER: silvio@conversation.port1024.net ----------------------------------------------------------------------------