From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from resqmta-po-10v.sys.comcast.net ([96.114.154.169]:39727 "EHLO resqmta-po-10v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754348AbaLIXNY (ORCPT ); Tue, 9 Dec 2014 18:13:24 -0500 Message-ID: <54878210.8030807@pobox.com> Date: Tue, 09 Dec 2014 15:13:20 -0800 From: Robert White MIME-Version: 1.0 To: Patrik Lundquist , "linux-btrfs@vger.kernel.org" Subject: Re: Fixing Btrfs Filesystem Full Problems typo? References: <20141122222606.GO8916@merlins.org> <20141123000503.GQ32735@carfax.org.uk> <20141123010742.GA16599@merlins.org> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 12/09/2014 02:29 PM, Patrik Lundquist wrote: > Label: none uuid: 770fe01d-6a45-42b9-912e-e8f8b413f6a4 > Total devices 1 FS bytes used 1.35TiB > devid 1 size 2.73TiB used 1.36TiB path /dev/sdc1 > > > Data, single: total=1.35TiB, used=1.35TiB > System, single: total=32.00MiB, used=112.00KiB > Metadata, single: total=3.00GiB, used=1.55GiB > GlobalReserve, single: total=512.00MiB, used=0.00B Are you trying to convert a filesystem on a single device/partition to RAID 1? I don't think thats legal. Whithout a second slice to distribute the copies of the data onto there is no raiding to be done. Add the second device with btrfs device add, and _then_ use balance to redistribute and copy the data to the second device. ASIDE: I, personally, think that a single device RAID1 should be legal. I also think that it should be possible to tell the system that you want N copies if you have N-or-more slices onto which they would spread. These would match my expectations from mdadm and several hardware and appliance RAID solutions. But my opinions in the matter do _not_ match the BTRFS code base. RAID1 means exactly two devices (for any given piece of information) [though I don't know whether it always has to be the _same_ two devices for two different pieces of information.] So yea, if that is what you are trying to do, the inability to find a second drive on which to allocate the peer-block(s) for an extent would produce interesting errors. I cant say for sure that this is the exact genesis of your issue, but I've read here in other threads a number of comments that would translate as "trying to set RAID1 with on a one-slice file system will be full of fail".