From: Andreas Dilger Subject: Re: resize2fs > 16TB questions Date: Thu, 2 Aug 2012 22:28:20 -0700 Message-ID: <250D8AFB-6442-4399-BBC5-2B37B5EC9B4B@whamcloud.com> References: <2019C80F-7D05-44FD-89AE-829E3A97053A@sportsandbytes.de> <2AD4EE0D-16C3-4D01-9A34-544E5D5FE8ED@whamcloud.com> <28D780F2-63AA-4FD8-B873-EBE3FD1DF3D3@sportsandbytes.de> <4DA51F27-D3C1-4867-9DC2-7040423E4BAD@whamcloud.com> <71E9EE6B-0615-4F22-9B7F-37D238F2D683@sportsandbytes.de> <82C4FEEB-5926-494D-B68D-6FAC530F098A@whamcloud.com> Mime-Version: 1.0 (1.0) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Justin Maggard , ext4 development To: Yongqiang Yang Return-path: Received: from mail-yw0-f46.google.com ([209.85.213.46]:33426 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751056Ab2HCF22 convert rfc822-to-8bit (ORCPT ); Fri, 3 Aug 2012 01:28:28 -0400 Received: by yhmm54 with SMTP id m54so383610yhm.19 for ; Thu, 02 Aug 2012 22:28:28 -0700 (PDT) In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: On 2012-08-02, at 19:36, Yongqiang Yang wrote: > In my memory, meta_bg is not allowed to set with resize_inode. So if > you want to use the patch, you need options > meta_bg,64bit,^resize_inode when mkfs. It is already default to disable resize_inode when 64bit is enabled, bu= t possibly this is only some for filesystems over 16TB. It might make sense to disable resize_inode when the filesystem is resi= zed to 16TB by resize2fs.=20 > I am busy on other things, so > I am a way the patch for a while. >=20 > On Fri, Aug 3, 2012 at 4:57 AM, Justin Maggard = wrote: >> On Thu, Aug 2, 2012 at 1:15 PM, Andreas Dilger wrote: >>>=20 >>> On 2012-07-29, at 12:08, Arne H=C3=BCggenberg wrote: >>>=20 >>>> On Jul 29, 2012, at 8:30 PM, Andreas Dilger wrote: >>>>>>> Unfortunately, the group descriptor size is not printed. >>>>>>=20 >>>>>> how can i get the group descriptor size? >>>>>=20 >>>>> Possibly with "debugfs stats"? >>>>=20 >>>> ~ # debugfs /dev/vg0/lvol1 >>>> debugfs 1.42.4 (12-June-2012) >>>> debugfs: stats >>>> debugfs: stats >>>>=20 >>>> 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_in= dex filetype extent 64bit flex_bg sparse_super large_file huge_file uni= nit_bg dir_nlink extra_isize >>>> Filesystem flags: signed_directory_hash >>>> 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: 2162482117 >>>> Free inodes: 520936736 >>>> 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 20:50:44 2012 >>>> Mount count: 6 >>>> Maximum mount count: -1 >>>> Last checked: Fri Jul 27 17:16:24 2012 >>>> Check interval: 0 () >>>> Lifetime writes: 7662 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 >>>> Directories: 6392 >>>> Group 0: block bitmap at 2049, inode bitmap at 2065, inode table = at 2081 >>>> 26585 free blocks, 4085 free inodes, 2 used directories, = 4084 unused inodes >>>> [Checksum 0x7d46] >>>> Group 1: block bitmap at 2050, inode bitmap at 2066, inode table = at 2337 >>>> 4634 free blocks, 4096 free inodes, 0 used directories, 4= 096 unused inodes >>>> [Inode not init, Checksum 0x97aa] >>>> Group 2: block bitmap at 2051, inode bitmap at 2067, inode table = at 2593 >>>> 1020 free blocks, 4096 free inodes, 0 used directories, 4= 096 unused inodes >>>> [Inode not init, Checksum 0x571f] >>>> Group 3: block bitmap at 2052, inode bitmap at 2068, inode table = at 2849 >>>> 2047 free blocks, 4096 free inodes, 0 used directories, 4= 096 unused inodes >>>=20 >>> Surprisingly, the group descriptor size is also not printed here. L= ooking at the code in mke2fs, it appears the 64-byte size used for file= systems when the 64bit flag is set, regardless of what size the filesys= tem is, and there is no way to change it. >>>=20 >>> It looks like my theory is wrong, but I don't have access to a syst= em to test this. Probably worthwhile to ask Yongqiang Yang (CC'd), who = wrote the 64-bit resize code. >>>=20 >>=20 >> I had the same confusion 11 months ago, when the 64-bit resize >> patchset was first posted, and I posted almost the same question her= e. >> My understanding at the end of the mailing list discussion was that >> you still cannot resize your filesystem beyond 16TB -- even if the >> 64bit flag is set -- and you may never be able to do so on that >> filesystem because you are using resize_inode and not meta_bg. Ther= e >> was a patchset posted on this list a few months ago by Yongquiang Ya= ng >> to do meta_bg expansion, but there hasn't been much action around it >> from what I have seen (maybe for the 3.7 merge window?). >>=20 >> You can read on here: >> http://permalink.gmane.org/gmane.comp.file-systems.ext4/27718 >>=20 >> -Justin >> -- >> 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 >=20 >=20 >=20 > --=20 > Best Wishes > Yongqiang Yang -- 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