From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.15.19]:60681 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932612Ab3CVM3e (ORCPT ); Fri, 22 Mar 2013 08:29:34 -0400 Received: from mailout-de.gmx.net ([10.1.76.1]) by mrigmx.server.lan (mrigmx001) with ESMTP (Nemesis) id 0MfCFw-1U46cA0b7K-00OmtC for ; Fri, 22 Mar 2013 13:29:32 +0100 Message-ID: <514C4EAA.8010908@gmx.net> Date: Fri, 22 Mar 2013 13:29:30 +0100 From: Arne Jansen MIME-Version: 1.0 To: Wang Shilong CC: linux-btrfs@vger.kernel.org, Koen De Wit Subject: Re: Adding a non-empty subvol to a qgroup References: <514C33A2.9050709@oracle.com> <3E907C97-0CAE-4A08-8866-C36BF2388FEC@gmail.com> In-Reply-To: <3E907C97-0CAE-4A08-8866-C36BF2388FEC@gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 22.03.2013 13:03, Wang Shilong wrote: > Hello Arne, > > Since "quota rescan" has not been implemented yet, > > overflow can happen, so until now, we can have a check when > doing accounting in the kernel, if the referenced/exclusive is not > enough to delete, we just make it to be 0 and give a warning. > > Otherwise, user may get a strange integer(because of type u64). > How do you think ? or we just wait for the implement of rescan. I think we already print it negatively. Please just leave it as it is. Thanks, Arne > > Thanks, > Wang > >> All, >> >> When adding a subvolume to a qgroup, pre-existing files in that subvolume are not counted in the referenced/exclusive space of the qgroup. Is this intended behavior ? >> >> I create a subvol with one file: >> >> # mkfs.btrfs /dev/sdg >> # mount /dev/sdg /mnt/fulldisk >> # cd /mnt/fulldisk >> # btrfs quota enable ./ >> # btrfs sub create sub1 >> # dd if=/dev/zero of=sub1/file1 bs=100000 count=1 >> # sync >> # btrfs qgroup show ./ >> 0/257 106496 106496 >> >> Now I create a new qgroup on level 1 and add the qgroup of sub1 to it : >> >> # btrfs qgroup create 1/0 ./ >> # btrfs qgroup assign 0/257 1/0 ./ >> # sync >> # btrfs fi sync ./ >> # btrfs quota rescan ./ >> # btrfs quota rescan ./sub1 >> # btrfs qgroup show ./ >> 0/257 106496 106496 >> 1/0 0 0 >> >> The pre-existing file does not contribute to the space numbers. >> >> Let's create a new file: >> >> # dd if=/dev/zero of=sub1/file2 bs=50000 count=1 >> # sync >> # btrfs qgroup show ./ >> 0/257 159744 159744 >> 1/0 53248 53248 >> >> We see that only the new file is included in the space numbers. >> >> Now I remove the first file: >> >> # rm -f sub1/file1 >> # sync >> # btrfs qgroup show ./ >> 0/257 57344 57344 >> 1/0 -49152 -49152 >> >> The space numbers go below zero. Even if the behavior above is intended, the removal of the pre-existing file should not result in negative space numbers. >> >> Koen. >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >