ext2, or second extended file system, is a file system for the Linux kernel. It was initially designed by French software developer Rémy Card as a replacement for the extended file system (ext). Having been designed according to the same principles as the Berkeley Fast File System from BSD, it was the first commercial-grade filesystem for Linux.
ext3, or third extended filesystem, is a journaled file system that is commonly used by the Linux kernel. It used to be the default file system for many popular Linux distributions. Stephen Tweedie first revealed that he was working on extending ext2 in Journaling the Linux ext2fs Filesystem in a 1998 paper, and later in a February 1999 kernel mailing list posting. The filesystem was merged with the mainline Linux kernel in November 2001 from 2.4.15 onward. Its main advantage over ext2 is journaling, which improves reliability and eliminates the need to check the file system after an unclean shutdown. Its successor is ext4.
The Syslinux Project is a suite of five different boot loaders for starting up Linux distros on computers. It was primarily developed by H. Peter Anvin.
In the maintenance of file systems, defragmentation is a process that reduces the degree of fragmentation. It does this by physically organizing the contents of the mass storage device used to store files into the smallest number of contiguous regions. It also attempts to create larger regions of free space using compaction to impede the return of fragmentation. Some defragmentation utilities try to keep smaller files within a single directory together, as they are often accessed in sequence.
Reiser4 is a computer file system, successor to the ReiserFS file system, developed from scratch by Namesys and sponsored by DARPA as well as Linspire. Reiser4 was named after its former lead developer Hans Reiser. As of 2021, the Reiser4 patch set is still being maintained, but according to Phoronix, it is unlikely to be merged into mainline Linux without corporate backing.
In computing, a file system or filesystem governs file organization and access. A local file system is a capability of an operating system that services the applications running on the same computer. A distributed file system is a protocol that provides file access between networked computers.
An AG or allocation group is a subvolume in a file system which maintains its own track of free blocks and file data.
In computing, an extent is a contiguous area of storage reserved for a file in a file system, represented as a range of block numbers, or tracks on count key data devices. A file can consist of zero or more extents; one file fragment requires one extent. The direct benefit is in storing each range compactly as two numbers, instead of canonically storing every block number in the range. Also, extent allocation results in less file fragmentation.
GParted is a GTK front-end to GNU Parted and an official GNOME partition-editing application. GParted is used for creating, deleting, resizing, moving, checking, and copying disk partitions and their file systems. This is useful for creating space for new operating systems, reorganizing disk usage, copying data residing on hard disks, and mirroring one partition with another. It can also be used to format a USB drive.
Extended file attributes are file system features that enable users to associate computer files with metadata not interpreted by the filesystem, whereas regular attributes have a purpose strictly defined by the filesystem. Unlike forks, which can usually be as large as the maximum file size, extended attributes are usually limited in size to a value significantly smaller than the maximum file size. Typical uses include storing the author of a document, the character encoding of a plain-text document, or a checksum, cryptographic hash or digital certificate, and discretionary access control information.
Enterprise Volume Management System (EVMS) was a flexible, integrated volume management software used to manage storage systems under Linux.
The following tables compare general and technical information for a number of file systems.
ext4 is a journaling file system for Linux, developed as the successor to ext3.
Partimage is a disk cloning utility for Linux/UNIX environments. Partimage can save partitions in many formats to a disk image. Utilities such as Partimage are useful in a number of situations which are commonly encountered by network administrators as well as advanced computer users who maintain their own systems. The last stable release was in 2010; since then, one of Partimage's authors has worked on FSArchiver, which has broader functionality than Partimage.
chattr is the command in Linux that allows a user to set certain attributes of a file. lsattr is the command that displays the attributes of a file.
Btrfs is a computer storage format that combines a file system based on the copy-on-write (COW) principle with a logical volume manager, developed together. It was founded by Chris Mason in 2007 for use in Linux, and since November 2013, the file system's on-disk format has been declared stable in the Linux kernel.
Clonezilla is an open-source suite of disk cloning, disk imaging and system deployment utilities. Clonezilla Server Edition uses multicast technologies to deploy a single image file to a group of computers on a local area network. Clonezilla was designed by Steven Shiau and developed by the NCHC Free Software Labs in Taiwan.
FSArchiver is a disk cloning utility for Linux. FSArchiver can save partitions containing different popular file systems to a disk image. It is a continuation of PartImage, which was a project from one of the same authors, and implements new features that PartImage lacks.
Partition-Saving is a disk imaging utility for Linux, Windows and DOS environments that can save disk partitions in one of the several supported disk image formats.
DMDE is a data recovery and disk editing tool for hard drives and other storage media. It can work with physical devices, logical disks, disk images, as well as RAID-arrays and recovers files that have been accidentally deleted or lost due to other incidents.
