From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.17.20]:60187 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755249AbaGUNWY (ORCPT ); Mon, 21 Jul 2014 09:22:24 -0400 Received: from marcec ([77.22.138.176]) by mail.gmx.com (mrgmx102) with ESMTPSA (Nemesis) id 0MdEsh-1WrxwT2eZv-00IWNe for ; Mon, 21 Jul 2014 15:22:22 +0200 Date: Mon, 21 Jul 2014 15:22:16 +0200 From: Marc Joliet To: linux-btrfs@vger.kernel.org Subject: Re: ENOSPC errors during balance Message-ID: <20140721152216.27d8a4c4@marcec> In-Reply-To: <20140720214440.398e7e68@marcec> References: <20140719172605.445e8445@marcec> <39E33553-3073-483E-9A2A-088212B40D0B@colorremedies.com> <20140720122233.4ef06751@marcec> <20140720134054.3cd6cef3@marcec> <20140720214440.398e7e68@marcec> Reply-To: linux-btrfs@vger.kernel.org MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/qZBRbNu/ED+QJQuE/h27X/S"; protocol="application/pgp-signature" Sender: linux-btrfs-owner@vger.kernel.org List-ID: --Sig_/qZBRbNu/ED+QJQuE/h27X/S Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Am Sun, 20 Jul 2014 21:44:40 +0200 schrieb Marc Joliet : [...] > What I did: >=20 > - delete the single largest file on the file system, a 12 GB VM image, al= ong > with all subvolumes that contained it > - rsync it over again [...] I want to point out at this point, though, that doing those two steps freed= a disproportionate amount of space. The image file is only 12 GB, and it had= n't changed in any of the snapshots (I haven't used this VM since June), so that "subvolume delete -c " returned after a few seconds. Yet deletin= g it seems to have freed up twice as much. You can see this from the "filesystem= df" output: before, "used" was at 229.04 GiB, and after deleting it and copying= it back (and after a day's worth of backups) went down to 218 GiB. Does anyone have any idea how this happened? Actually, now I remember something that is probably related: when I first moved to my current backup scheme last week, I first copied the data from t= he last rsnapshot based backup with "cp --reflink" to the new backup location,= but forgot to use "-a". I interrupted it and ran "cp -a -u --reflink", but it = had already copied a lot, and I was too impatient to start over; after all, the data hadn't changed. Then, when rsync (with --inplace) ran for the first t= ime, all of these files with wrong permissions and different time stamps were co= pied over, but for some reason, the space used increased *greatly*; *much* more = than I would expect from changed metadata. The total size of the file system data should be around 142 GB (+ snapshots= ), but, well, it's more than 1.5 times as much. Perhaps cp --reflink treats hard links differently than expected? I would = have expected the data pointed to by the hard link to have been referenced, but maybe something else happened? --=20 Marc Joliet -- "People who think they know everything really annoy those of us who know we don't" - Bjarne Stroustrup --Sig_/qZBRbNu/ED+QJQuE/h27X/S Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBAgAGBQJTzRQNAAoJEL/Q5oYsiHj0r+wP/3LxqhmDxYTm3HC5QU/cSR8b aHWUwO90N16QiPajUeUMOUVJPjrw6KmCAbGtxKlUg4iJoomqzFWf8i2WEOGAlfX1 KPzdrq2TDkZTeH1Q5HIWlHpM1VgYyT0BJHO6YnWzO5qcLpyPG9vVSDiRPUqWI2KJ 8NMsInF4V3274NYwH4fZoHmGAyztzJ2t/qZffoaTp2BFtNhP7LCWH27c4GWvOitZ v1RA/wU8RvrHCPYNeang60W4t0C403OIOgLt/z7fhC6KAIRrh6yM4J5BSCaIca/X joelPMGO6TjUuBeIyuIGevgdItKAper1UNkKKTFqteNuSai0iycYP2WUopnHBQK4 3Y7iP0RJLk6ZBpcutR/qmE/OyZrkLgW16SEg8QFznAg1t62zv28fdbXaEK9YjqSk 9k8b+/FYq4eSlfJz2WCJblGxovC2sAga0+8XRw28vbn/0jo1mpIealCqPe49ow3R AWz1rRtnzE+UD0a+iHbGsLtnoyJi15vgUc//pSlNNdIgy1N19PE8h3yH+9cMn86y QlL7XMD07CO0TL0yXtk8pnmyflaFJERWL7AP0TR5Ro6OXHF0IpPpJ9OjCnExihpA 1MMqg8Yb3Dds+0qJFIAjm1D8c3VTbl3DzKdjopYiJrxp0zvSQ9rBryKA1dXqS5EL plifVsb8sk4bnkHwnyyh =obgG -----END PGP SIGNATURE----- --Sig_/qZBRbNu/ED+QJQuE/h27X/S--