From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.15.19]:52242 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753179AbaGUWbG (ORCPT ); Mon, 21 Jul 2014 18:31:06 -0400 Received: from marcec ([77.22.138.176]) by mail.gmx.com (mrgmx002) with ESMTPSA (Nemesis) id 0LanoO-1Wgf7Q1dTE-00kOEn for ; Tue, 22 Jul 2014 00:31:04 +0200 Date: Tue, 22 Jul 2014 00:30:57 +0200 From: Marc Joliet To: linux-btrfs@vger.kernel.org Subject: Re: ENOSPC errors during balance Message-ID: <20140722003057.0f3b89f0@marcec> In-Reply-To: <20140721152216.27d8a4c4@marcec> References: <20140719172605.445e8445@marcec> <39E33553-3073-483E-9A2A-088212B40D0B@colorremedies.com> <20140720122233.4ef06751@marcec> <20140720134054.3cd6cef3@marcec> <20140720214440.398e7e68@marcec> <20140721152216.27d8a4c4@marcec> Reply-To: linux-btrfs@vger.kernel.org MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/EWZ+L=XK/94m9w_m=z4nSPK"; protocol="application/pgp-signature" Sender: linux-btrfs-owner@vger.kernel.org List-ID: --Sig_/EWZ+L=XK/94m9w_m=z4nSPK Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Am Mon, 21 Jul 2014 15:22:16 +0200 schrieb Marc Joliet : > Am Sun, 20 Jul 2014 21:44:40 +0200 > schrieb Marc Joliet : >=20 > [...] > > What I did: > >=20 > > - delete the single largest file on the file system, a 12 GB VM image, = along > > with all subvolumes that contained it > > - rsync it over again > [...] >=20 > I want to point out at this point, though, that doing those two steps fre= ed a > disproportionate amount of space. The image file is only 12 GB, and it h= adn't > changed in any of the snapshots (I haven't used this VM since June), so t= hat > "subvolume delete -c " returned after a few seconds. Yet delet= ing it > seems to have freed up twice as much. You can see this from the "filesyst= em df" > output: before, "used" was at 229.04 GiB, and after deleting it and copyi= ng it > back (and after a day's worth of backups) went down to 218 GiB. >=20 > Does anyone have any idea how this happened? >=20 > 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= the > last rsnapshot based backup with "cp --reflink" to the new backup locatio= n, but > forgot to use "-a". I interrupted it and ran "cp -a -u --reflink", but i= t had > already copied a lot, and I was too impatient to start over; after all, t= he > data hadn't changed. Then, when rsync (with --inplace) ran for the first= time, > all of these files with wrong permissions and different time stamps were = copied > over, but for some reason, the space used increased *greatly*; *much* mor= e than > I would expect from changed metadata. >=20 > The total size of the file system data should be around 142 GB (+ snapsho= ts), > but, well, it's more than 1.5 times as much. >=20 > Perhaps cp --reflink treats hard links differently than expected? I woul= d have > expected the data pointed to by the hard link to have been referenced, but > maybe something else happened? Hah, OK, apparently when my daily backup removed the oldest daily snapshot,= it freed up whatever was taking up so much space, so as of now the file system uses only 169.14 GiB (from 218). Weird. --=20 Marc Joliet -- "People who think they know everything really annoy those of us who know we don't" - Bjarne Stroustrup --Sig_/EWZ+L=XK/94m9w_m=z4nSPK Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBAgAGBQJTzZSmAAoJEL/Q5oYsiHj0Nq4P/1lyNC638XIZ/m835vEYDx41 V/bWxdS3ZDTwzK9G1n3YayBtFoolTMSHvKI6VIBmY9O5Lo/vg9Z1AW5LjHEuXGxk UFJJ8x1mjJvFPKZ67HPy5ROInW9SdHGWGhMByuHnygfDAJ2Bg7VUMP8YwQBNisdv xoY/hfaHpPOY7+/DjtUK7PueMsh7Op0l3gxT9neCin4aeh9FdX8CLA2na9p2VsIk V4g965S9yikGlas5ZiwGKte8liQUU8x4EG4KGM7wSN73ryVpl1ZjMiRhGypsC2PR JRxLVNFMprcnkzh/i4tUck4MrA3rDbZtL0eVkjm8/+/zVtiqYfH2CatKl7UsSg2/ yU8TcPAvSNSenH6o9aBoNQdZ/2LosqYhp1BZrUL8dUfsHqkTMnOJD0Pz3/+L9QhH 1bWqXmpTLdQKpGJzyUkB1lzdejNflyvtXLavfucTJNpTsTHzSB4/W3iY6H0eQpuo AHDN+qp5VtrUo6OgtkQZc09MuNQnlbyYvdg45pu+nioX3GHFZ+p5ZZsmyOvyFADg 9B9rhXXwzuYtCpxoC6VuMm/45bvppRGd/bKZz40ZyTldFvTrdACxXRXEgM8KnP3A ECs7os1ugPaCTuwrliimuVUF4eWTlvA1c7ydoohk88ndCM53hlZwDWFP/uXaJHzI kWS6DIdeY82t9AKVUTz2 =7HTg -----END PGP SIGNATURE----- --Sig_/EWZ+L=XK/94m9w_m=z4nSPK--