XFS is a high-performance 64-bit journaling file system created by Silicon Graphics, Inc (SGI) in 1993. It was the default file system in SGI's IRIX operating system starting with its version 5.3. XFS was ported to the Linux kernel in 2001; as of June 2014, XFS is supported by most Linux distributions; Red Hat Enterprise Linux uses it as its default file system.
ext3, or third extended filesystem, is a journaled file system that is commonly used with the Linux kernel. It used to be the default file system for many popular Linux distributions but generally has been supplanted by its successor version ext4. The main advantage of ext3 over its predecessor, ext2, is journaling, which improves reliability and eliminates the need to check the file system after an improper, a.k.a. unclean, shutdown.
Journaled File System (JFS) is a 64-bit journaling file system created by IBM. There are versions for AIX, OS/2, eComStation, ArcaOS and Linux operating systems. The latter is available as free software under the terms of the GNU General Public License (GPL). HP-UX has another, different filesystem named JFS that is actually an OEM version of Veritas Software's VxFS.
RAID is a data storage virtualization technology that combines multiple physical data storage components into one or more logical units for the purposes of data redundancy, performance improvement, or both. This is in contrast to the previous concept of highly reliable mainframe disk drives known as single large expensive disk (SLED).
Hierarchical File System (HFS) is a proprietary file system developed by Apple Inc. for use in computer systems running Mac OS. Originally designed for use on floppy and hard disks, it can also be found on read-only media such as CD-ROMs. HFS is also referred to as Mac OS Standard, while its successor, HFS Plus, is also called Mac OS Extended.
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.
The inode is a data structure in a Unix-style file system that describes a file-system object such as a file or a directory. Each inode stores the attributes and disk block locations of the object's data. File-system object attributes may include metadata, as well as owner and permission data.
A disk quota is a limit set by a system administrator that restricts certain aspects of file system usage on modern operating systems. The function of using disk quotas is to allocate limited disk space in a reasonable way.
The Amiga Fast File System is a file system used on the Amiga personal computer from the computer-manufacturer Commodore Int'l.. The previous Amiga filesystem was never given a specific name and known originally simply as "DOS" or AmigaDOS. Upon the release of FFS and for purposes of differentiation, the original filesystem became retrospectively known as Amiga's Old File System, shortened OFS. The former file-system OFS, which was primarily designed for use with floppy disks, had been proving slow to keep up with hard drives of the era.
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.
The VERITAS File System is an extent-based file system. It was originally developed by VERITAS Software. Through an OEM agreement, VxFS is used as the primary filesystem of the HP-UX operating system. With on-line defragmentation and resize support turned on via license, it is known as OnlineJFS. It is also supported on AIX, Linux, Solaris, OpenSolaris, SINIX/Reliant UNIX, UnixWare and SCO OpenServer. VxFS was originally developed for AT&T's Unix System Laboratories. VxFS is packaged as a part of the Veritas Storage Foundation.
Allocate-on-flush is a file system feature implemented in HFS+, XFS, Reiser4, ZFS, Btrfs, and ext4. The feature also closely resembles an older technique that Berkeley's UFS called "block reallocation".
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.
In Linux, Logical Volume Manager (LVM) is a device mapper framework that provides logical volume management for the Linux kernel. Most modern Linux distributions are LVM-aware to the point of being able to have their root file systems on a logical volume.
Replication in computing refers to maintaining multiple copies of data, processes, or resources to ensure consistency across redundant components. This fundamental technique spans databases, file systems, and distributed systems, serving to improve availability, fault-tolerance, accessibility, and performance. Through replication, systems can continue operating when components fail (failover), serve requests from geographically distributed locations, and balance load across multiple machines. The challenge lies in maintaining consistency between replicas while managing the fundamental tradeoffs between data consistency, system availability, and network partition tolerance – constraints known as the CAP theorem.
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.
In computing, file system fragmentation, sometimes called file system aging, is the tendency of a file system to lay out the contents of files non-continuously to allow in-place modification of their contents. It is a special case of data fragmentation. File system fragmentation negatively impacts seek time in spinning storage media, which is known to hinder throughput. Fragmentation can be remedied by re-organizing files and free space back into contiguous areas, a process called defragmentation.
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 created 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.
StorNext File System (SNFS), colloquially referred to as StorNext is a shared disk file system made by Quantum Corporation. StorNext enables multiple Windows, Linux and Apple workstations to access shared block storage over a Fibre Channel network. With the StorNext file system installed, these computers can read and write to the same storage volume at the same time enabling what is known as a "file-locking SAN." StorNext is used in environments where large files must be shared, and accessed simultaneously by users without network delays, or where a file must be available for access by multiple readers starting at different times. Common use cases include multiple video editor environments in feature film, television and general video post production.
