From: Andreas Dilger Subject: Re: resize2fs > 16TB questions Date: Sun, 29 Jul 2012 09:11:03 -0700 Message-ID: <2AD4EE0D-16C3-4D01-9A34-544E5D5FE8ED@whamcloud.com> References: <2019C80F-7D05-44FD-89AE-829E3A97053A@sportsandbytes.de> Mime-Version: 1.0 (1.0) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "linux-ext4@vger.kernel.org" To: =?utf-8?Q?Arne_H=C3=BCggenberg?= Return-path: Received: from mail-ob0-f174.google.com ([209.85.214.174]:39967 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753275Ab2G2QLZ convert rfc822-to-8bit (ORCPT ); Sun, 29 Jul 2012 12:11:25 -0400 Received: by obbuo13 with SMTP id uo13so7575823obb.19 for ; Sun, 29 Jul 2012 09:11:24 -0700 (PDT) In-Reply-To: <2019C80F-7D05-44FD-89AE-829E3A97053A@sportsandbytes.de> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 2012-07-29, at 8:24, Arne H=C3=BCggenberg wrote: >=20 > im trying to resize a ext4 fs to > 16TB. Unfortunately, this is not possible today without advance planning. Th= ere are some structures on disk (group descriptors) that need to be lar= ger for 64-bit filesystems. It is possible to format a 32-bit filesyste= m with larger group descriptors using the "-O 64bit" option, but this d= oesn't happen by default today.=20 Possibly we should start using the 64-byte group descriptors by default= for filesystems over, say, 4 TB, so they can be resized beyond 16 TB. It might also be possible to modify resize2fs to change the group descr= iptor size, but that isn't possible today.=20 > Having had a look at the e2fsprogs 1.42.x release notes i thought tha= t, with the online resize ioctl having been merged in Kernel 3.3, this = should be possible. >=20 > But so far i have had no success achieving this: >=20 > ~ # uname -a > Linux 3.3.8-gentoo #1 SMP Fri Jul 27 16:13:25 CEST 2012 x86_64 Intel(= R) Xeon(R) CPU E5620 @ 2.40GHz GenuineIntel GNU/Linux >=20 > ~ # tune2fs -l /dev/vg0/lvol1 > tune2fs 1.42.4 (12-June-2012) > Filesystem volume name: > Last mounted on: /home/filestore_extern_1 > Filesystem UUID: 8fba4f1b-5311-4c9b-b8bf-def4957dc1bd > Filesystem magic number: 0xEF53 > Filesystem revision #: 1 (dynamic) > Filesystem features: has_journal ext_attr resize_inode dir_index= filetype needs_recovery extent 64bit flex_bg sparse_super large_file h= uge_file uninit_bg dir_nlink extra_isize Was the filesystem formatted with the 64bit option, or was this enabled= after formatting time? This puts my earlier comment in doubt.=20 > Filesystem flags: signed_directory_hash=20 > Default mount options: user_xattr acl > Filesystem state: clean > Errors behavior: Continue > Filesystem OS type: Linux > Inode count: 521011200 > Block count: 4168089600 > Reserved block count: 191127425 > Free blocks: 2195165566 > Free inodes: 520937830 > First block: 0 > Block size: 4096 > Fragment size: 4096 > Reserved GDT blocks: 60 > Blocks per group: 32768 > Fragments per group: 32768 > Inodes per group: 4096 > Inode blocks per group: 256 > RAID stride: 16 > RAID stripe width: 160 > Flex block group size: 16 > Filesystem created: Fri Jul 27 17:16:24 2012 > Last mount time: Sun Jul 29 15:22:23 2012 > Last write time: Sun Jul 29 15:22:23 2012 > Mount count: 6 > Maximum mount count: -1 > Last checked: Fri Jul 27 17:16:24 2012 > Check interval: 0 () > Lifetime writes: 7485 GB > Reserved blocks uid: 0 (user root) > Reserved blocks gid: 0 (group root) > First inode: 11 > Inode size: 256 > Required extra isize: 28 > Desired extra isize: 28 > Journal inode: 8 > Default directory hash: half_md4 > Directory Hash Seed: ef2ec72a-750b-4822-bd8d-9117faadeaee > Journal backup: inode blocks Unfortunately, the group descriptor size is not printed. =20 > ~ # vgdisplay > --- Volume group --- > VG Name vg0 > System ID =20 > Format lvm2 > Metadata Areas 2 > Metadata Sequence No 4 > VG Access read/write > VG Status resizable > MAX LV 0 > Cur LV 1 > Open LV 1 > Max PV 0 > Cur PV 2 > Act PV 2 > VG Size 18.18 TiB > PE Size 4.00 MiB > Total PE 4766718 > Alloc PE / Size 4766718 / 18.18 TiB > Free PE / Size 0 / 0 =20 > VG UUID q6p5LG-pi1P-pAcI-fSsv-vFI7-6sAA-eabaBH >=20 > ~ # lvdisplay > --- Logical volume --- > LV Name /dev/vg0/lvol1 > VG Name vg0 > LV UUID 7OF1do-HqZD-FGSN-chJF-rPYC-x1Ty-vGCZlc > LV Write Access read/write > LV Status available > # open 1 > LV Size 18.18 TiB > Current LE 4766718 > Segments 2 > Allocation inherit > Read ahead sectors auto > - currently set to 256 > Block device 254:1 >=20 > ~ # resize2fs /dev/vg0/lvol1 > resize2fs 1.42.4 (12-June-2012) > resize2fs: New size too large to be expressed in 32 bits This may just be a hard-coded check built into resize2fs, but may be ov= er-zealous of the filesystem was formatted with -O 64bit.=20 > Any advice on how to proceed would be welcome. >=20 > Regards, > Arne >=20 >=20 >=20 >=20 >=20 >=20 > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html