EXT2(5) EXT2(5) (NAME) ext2 - (second extended file system) (DESCRIPTION) ext2 . ext2 ext3 ext4 . . ext2 ext3 ext4 ext4 ext2 ext3 . (FILE SYSTEM FEATURES) ext2 ext3 ext4 . ext2 ext3 ext4 . GNU/HURD FreeBSD ext2 . 64bit ^ . ^ . e2fsprogs ext4 . bigalloc ext4 . . . -C mke2fs . : bigalloc . http://ext4.wiki.kernel.org/index.php/Bigalloc . ( nodelalloc ). extent . casefold ext4 casefold (+F) . . dir_index B (hashed b-trees) . ext3 ext4 ext2 . dir_nlink ext4 , . , ( '.' '..' ). ext4 . ea_inode . . encrypt . ( / ) . dm-crypt . ext_attr . ext2 ext3 ext4 . extent ext4 (extent tree) ext2 ext3 . e2fsck(8) . (: extent extents .) extra_isize ext4 . . . filetype . ext2 ext3 ext4 . flex_bg ext4 ( ) . mke2fs " flex_bg" . flex_bg -G . has_journal . -j mke2fs tune2fs . ext3 ext4 ext2 . huge_file ext4 . inline_data . journal_dev . . -J device=<-> mke2fs(8) tune2fs(8) . large_dir B ( dir_index) B . large_file . . metadata_csum ext4 . ( ) . uninit_bg . metadata_csum uninit_bg . metadata_csum_seed UUID metadata_csum . meta_bg ext4 (on-line) . ^ . . mmp ext4 (Multiple Mount Protection MMP) . MMP . orphan_file ext4 (truncate) . . e2fsprogs .. . project ext4 (project quota) . (project ID) . quota ( ) . . ( user.quota group.quota ) . resize_inode . resize2fs(8) . mke2fs . resize . sparse_super sparse_super2 . sparse_super ext2 ext3 ext4 . . sparse_super2 . () () . sparse_super . stable_inodes UUID (stable) . resize2fs(8) tune2fs(8) UUID . UUID . encrypt . stable_inodes ("compat") . uninit_bg ext4 mke2fs(8) . (lazy) . e2fsck(8) mke2fs(8) . verity verity . verity (Merkle tree) . verity . - . dm-verity . (MOUNT OPTIONS) ext2 ext3 ext4 . mount(8) . ext2 (Mount options for ext2) `ext2' . .. . tune2fs(8) . acl|noacl (POSIX Access Control Lists) . acl(5) . bsddf|minixdf statfs. minixdf f_blocks bsddf ( ) ext2 . : % mount /k -o minixdf; df /k; umount /k File System 1024-blocks Used Available Capacity Mounted on /dev/sda6 2630655 86954 2412169 3% /k % mount /k -o bsddf; df /k; umount /k File System 1024-blocks Used Available Capacity Mounted on /dev/sda6 2543714 13 2412169 0% /k ( /etc/fstab .) check=none nocheck . . e2fsck(8) . ( check=normal check=strict ). ext4 ext2 ext3 . debug ( ). errors={continue|remount-ro|panic} . ( (panic) .) tune2fs(8) . grpid|bsdgroups nogrpid|sysvgroups (GID) . grpid () fsgid setgid gid setgid . grpquota|noquota|quota|usrquota usrquota ( quota) . grpquota . . nouid32 UID GID. . oldalloc orlov Orlov . Orlov . resgid=n resuid=n ext2 ( mke2fs(8) tune2fs(8)). ( : uid ). sb=n n . . sparse_super . mke2fs -n mke2fs ( sparse_super ). . "sb=131072" . user_xattr|nouser_xattr "user." ( ). ext3 (Mount options for ext3) ext3 ext2 . ext2 : journal_dev=devnum/journal_path=path / (major/minor) . / devnum . norecovery/noload . . data={journal|ordered|writeback} . . ordered rootflags=data=journal. journal . ordered . . writeback - . . . data_err=ignore ordered . data_err=abort ordered (abort). barrier=0 / barrier=1 (write barriers) jbd / . barrier=0 barrier=1 (). / jbd . . . commit=nrsec nrsec . . . user_xattr (Extended User Attributes). attr(5) . jqfmt={vfsold|vfsv0|vfsv1} ( ext2 jqfmt=vfsold ) ext3 ( ) . jqfmt=vfsv0 jqfmt=vfsv1 . . quota . usrjquota=aquota.user|grpjquota=aquota.group (jqfmt=vfsv0 jqfmt=vfsv1) usrjquota=aquota.user grpjquota=aquota.group . quota . ext4 (Mount options for ext4) ext4 ext3 . journal_dev, journal_path, norecovery, noload, data, commit, orlov, oldalloc, [no]user_xattr, [no]acl, bsddf, minixdf, debug, errors, data_err, grpid, bsdgroups, nogrpid, sysvgroups, resgid, resuid, sb, quota, noquota, nouid32, grpquota, usrquota, usrjquota, grpjquota, jqfmt ext3 ext2 . journal_checksum | nojournal_checksum journal_checksum . e2fsck . . journal_async_commit commit . . 'journal_checksum' . barrier=0 / barrier=1 / barrier / nobarrier ext3 . "barrier" "nobarrier" ext4 . ext4 . inode_readahead_blks=n (readahead) ext4 . . . stripe=n mballoc . RAID5/6 (chunk) RAID . delalloc (write-out). nodelalloc . . max_batch_time=usec ext4 . commit I/O . ( ) . " " (commit time) . ext4 . max_batch_time ( ) . max_batch_time . min_batch_time=usec ( ) min_batch_time . . (latency) . journal_ioprio=prio I/O ( ) I/O kjournald2 commit . I/O . abort ext4_abort() . . auto_da_alloc|noauto_da_alloc : fd = open("foo.new")/write(fd,...)/close(fd)/ rename("foo.new", "foo") : fd = open("foo", O_TRUNC)/write(fd,...)/close(fd). fsync() . auto_da_alloc ext4 data=ordered rename() . ext3 " " (zero-length) . noinit_itable . . init_itable=n itable n . . discard/nodiscard ext4 discard/TRIM . SSD LUN / (thin-provisioned) . block_validity/noblock_validity / . . . dioread_lock/dioread_nolock ext4 DIO . dioread_nolock ext4 IO . ext4 (mutex) . dioread_nolock . dioread_nolock . ( dioread_lock ). max_dir_size_kb=n ENOSPC . (Out Of Memory killer) . ( .) i_version . . nombcache mbcache (deduplication) . mbcache . prjquota prjquota . . project . (FILE ATTRIBUTES) ext2 ext3 ext4 chattr(1) : a - (append only) A - atime d - dump D - i - (immutable) S - (synchronous updates) u - (undeletable) ext3 ext4 : j - ext4 : e - (extents format) chattr(1) . (KERNEL SUPPORT) ( ext2 ext3 ext4) . . . (backport) (Enterprise) . filetype ext2, 2.2.0 sparse_super ext2, 2.2.0 large_file ext2, 2.2.0 has_journal ext3, 2.4.15 ext_attr ext2/ext3, 2.6.0 dir_index ext3, 2.6.0 resize_inode ext3, 2.6.10 (online resizing) 64bit ext4, 2.6.28 dir_nlink ext4, 2.6.28 extent ext4, 2.6.28 extra_isize ext4, 2.6.28 flex_bg ext4, 2.6.28 huge_file ext4, 2.6.28 meta_bg ext4, 2.6.28 uninit_bg ext4, 2.6.28 mmp ext4, 3.0 bigalloc ext4, 3.2 quota ext4, 3.6 inline_data ext4, 3.8 sparse_super2 ext4, 3.16 metadata_csum ext4, 3.18 encrypt ext4, 4.1 metadata_csum_seed ext4, 4.4 project ext4, 4.5 ea_inode ext4, 4.13 large_dir ext4, 4.13 casefold ext4, 5.2 verity ext4, 5.4 stable_inodes ext4, 5.5 (SEE ALSO) mke2fs(8), mke2fs.conf(5), e2fsck(8), dumpe2fs(8), tune2fs(8), debugfs(8), mount(8), chattr(1) e2fsprogs EXT2(5)