From mboxrd@z Thu Jan 1 00:00:00 1970 From: Contact Subject: Re: Make huge files strictly contiguous (fallocate, bigalloc, e4defrag...) Date: Sun, 20 Apr 2014 21:38:30 +0200 Message-ID: <53542236.9030201@ovh.fr> References: <534F39F6.2000208@ovh.fr> <20140417152457.GE18591@thunk.org> <5350205E.3030403@ovh.fr> <5353DBC2.5080708@ovh.fr> <20140420190146.GB29727@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: =?UTF-8?B?THVrw6HFoSBDemVybmVy?= , "linux-ext4@vger.kernel.org" To: Theodore Ts'o Return-path: Received: from mo29.mail-out.ovh.net ([178.32.228.29]:52756 "EHLO mo29.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752835AbaDTTic (ORCPT ); Sun, 20 Apr 2014 15:38:32 -0400 In-Reply-To: <20140420190146.GB29727@thunk.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: Le dim. 20 avril 2014 21:01:46 CEST, Theodore Ts'o a =C3=A9crit : > > This requires recompiling e2fsprogs using the tip of the maint branch= , > as I had suggested earlier (and which you had ruled out because you > didn't want to build your own e2fsprogs from source). > Thanks, that explains why I wasn't able to find this option in regular=20 e2fsprogs. > Once you do this, and you put the following in > > hugefiles =3D { > features =3D extent,huge_file,flex_bg,uninit_bg,dir_nlink,extra_isi= ze,^resize_inode,sparse_super2 > hash_alg =3D half_md4 > num_backup_sb =3D 0 > packed_meta_blocks =3D 1 > flex_bg_size =3D 262144 > inode_ratio =3D 4194304 > make_hugefiles =3D 1 > hugefiles_dir =3D /boot > hugefiles_name =3D contig-files > hugefiles_digits =3D 1 > hugefiles_size =3D 256M > num_hugefiles =3D 3 > } > > Using the sparse_super2 feature and setting num_backup_sb=3D0 disable= s > the backup superblocks. Then setting flex_bg_size to a very large > value (262144 in this case), will force all of the allocation bitmaps > and inodetables to the very beginning of the file system. > The tip and stanza look very useful though, I'll reconsider retrieving=20 and compiling maint branch to try, thanks. > Note that because this uses a new compat feature, "sparse_super2", if > you use the new mke2fs to create such a file system, you will also > need to make sure the file system is checked using a version of e2fsc= k > that supports this new feature as well. No kernel changes are > required to support this, though. > Any plans to get this feature into master at some point in the=20 development? --Bastien -- 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