The following lists identify, characterize, and link to more thorough information on

Computer file A computer file is a computer resource for recording data in a computer storage device, primarily identified by its file name. Just as words can be written to paper, so can data be written to a computer file. Files can be shared with and trans ...

systems. Many older

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

s support only their one "native" file system, which does not bear any name apart from the name of the operating system itself.

Disk file systems

Disk file systems are usually block-oriented. Files in a block-oriented file system are sequences of blocks, often featuring fully random-access read, write, and modify operations. * ADFS –

Acorn The acorn, or oaknut, is the nut of the oaks and their close relatives (genera '' Quercus'' and ''Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and bo ...

's Advanced Disc filing system, successor to

DFS DFS may refer to: Brands and enterprises * Dancer Fitzgerald Sample, advertising agency, now Saatchi & Saatchi * DFS Furniture, a furniture retailer in the United Kingdom and Ireland * DFS Group (Duty Free Shoppers), Hong Kong * DFS Program Excha ...

. * AdvFS – Advanced File System, designed by

Digital Equipment Corporation Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president unti ...

for their Digital UNIX (now Tru64 UNIX) operating system. * APFS – Apple File System is a next-generation file system for Apple products. * AthFS – AtheOS File System, a 64-bit journaled filesystem now used by Syllable. Also called AFS. * BFS – the Boot File System used on System V release 4.0 and UnixWare. * BFS – the Be File System used on

BeOS BeOS is an operating system for personal computers first developed by Be Inc. in 1990. It was first written to run on BeBox hardware. BeOS was positioned as a multimedia platform that could be used by a substantial population of desktop users a ...

, occasionally misnamed as BeFS. Open source implementation called OpenBFS is used by the

Haiku is a type of short form poetry originally from Japan. Traditional Japanese haiku consist of three phrases that contain a ''kireji'', or "cutting word", 17 ''On (Japanese prosody), on'' (phonetic units similar to syllables) in a 5, 7, 5 pattern, ...

operating system. * Byte File System (BFS) - file system used by z/VM for Unix applications *

Btrfs Btrfs (pronounced as "better F S", "butter F S", "b-tree F S", or simply by spelling it out) is a computer storage format that combines a file system based on the copy-on-write (COW) principle with a logical volume manager (not to be confused ...

– is a

copy-on-write Copy-on-write (COW), sometimes referred to as implicit sharing or shadowing, is a resource-management technique used in computer programming to efficiently implement a "duplicate" or "copy" operation on modifiable resources. If a resource is dupl ...

file system for

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...

announced by

Oracle An oracle is a person or agency considered to provide wise and insightful counsel or prophetic predictions, most notably including precognition of the future, inspired by deities. As such, it is a form of divination. Description The wor ...

in 2007 and published under the

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end user In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ulti ...

(GPL). *

CFS CFS is an acronym for: Organizations * Canadian Federation of Students * Canadian Forest Service * Center for Financial Studies, a research institute affiliated with Goethe University Frankfurt * Center for Subjectivity Research, a research insti ...

– The Cluster File System from Veritas, a Symantec company. It is the parallel access version of VxFS. * CP/M file system — Native filesystem used in the CP/M (Control Program for Microcomputers) operating system which was first released in 1974. * DOS 3.x – Original floppy operating system and file system developed for the

Apple II The Apple II (stylized as ) is an 8-bit home computer and one of the world's first highly successful mass-produced microcomputer products. It was designed primarily by Steve Wozniak; Jerry Manock developed the design of Apple II's foam-mold ...

. * Extent File System (EFS) – an older block filing system under IRIX. * ext – Extended file system, designed for

systems. * ext2 – Second extended file system, designed for

systems. * ext3 – A journaled form of ext2. *

ext4 ext4 (fourth extended filesystem) is a journaling file system for Linux, developed as the successor to ext3. ext4 was initially a series of backward-compatible extensions to ext3, many of them originally developed by Cluster File Systems fo ...

– A follow up for ext3 and also a journaled filesystem with support for extents. * ext3cow – A versioning file system form of ext3. * FAT – File Allocation Table, initially used on DOS and Microsoft Windows and now widely used for portable USB storage and some other devices; FAT12, FAT16 and

FAT32 File Allocation Table (FAT) is a file system developed for personal computers. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. It is often supported for compatibility reasons by ...

for 12-, 16- and

32-bit In computer architecture, 32-bit computing refers to computer systems with a processor, memory, and other major system components that operate on data in 32- bit units. Compared to smaller bit widths, 32-bit computers can perform large calcula ...

table depths. ** VFAT – Optional layer on Microsoft Windows FAT system to allow long (up to 255 character) filenames instead of only the 8.3 filenames allowed in the plain FAT filesystem. **

FATX File Allocation Table (FAT) is a file system developed for personal computers. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. It is often supported for compatibility reasons by ...

– A modified version of Microsoft Windows FAT system that is used on the original

Xbox Xbox is a video gaming brand created and owned by Microsoft. The brand consists of five video game consoles, as well as applications (games), streaming services, an online service by the name of Xbox network, and the development arm by th ...

console. * FFS (Amiga) – Fast File System, used on

Amiga Amiga is a family of personal computers introduced by Commodore International, Commodore in 1985. The original model is one of a number of mid-1980s computers with 16- or 32-bit processors, 256 KB or more of RAM, mouse-based GUIs, and sign ...

systems. This FS has evolved over time. Now counts FFS1, FFS Intl, FFS DCache, FFS2. * FFS – Fast File System, used on * BSD systems *

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

– Plan 9 from Bell Labs snapshot archival file system. * Files-11 –

OpenVMS OpenVMS, often referred to as just VMS, is a multi-user, multiprocessing and virtual memory-based operating system. It is designed to support time-sharing, batch processing, transaction processing and workstation applications. Customers using Ope ...

file system; also used on some

PDP-11 The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were so ...

systems; supports record-oriented files * Flex machine file system * HAMMER — clustered

DragonFly BSD DragonFly BSD is a free and open-source Unix-like operating system forked from FreeBSD 4.8. Matthew Dillon, an Amiga developer in the late 1980s and early 1990s and FreeBSD developer between 1994 and 2003, began working on DragonFly BSD in ...

filesystem, production-ready since DragonFly 2.2 (2009) * HAMMER2 — recommended as the default root filesystem in DragonFly since 5.2 release in 2018 *

HFS HFS may refer to: Computing * Hardware functionality scan, a security mechanism used in Microsoft Windows operating systems * Hierarchical File System, a file system used by Apple Macintosh computers * Hierarchical File System (IBM MVS), used MV ...

– Hierarchical File System in IBM's z/OS; not to be confused with Apple's HFS. HFS is still supported but IBM's stated direction is zFS. *

– Hierarchical File System, in use until HFS+ was introduced on Mac OS 8.1. Also known as Mac OS Standard format. Successor to Macintosh File System (MFS) & predecessor to HFS+; not to be confused with IBM's HFS provided with z/OS * HFS+ – Updated version of Apple's HFS, Hierarchical File System, supported on Mac OS 8.1 & above, including macOS. Supports file system journaling, enabling recovery of data after a system crash. Also referred to as 'Mac OS Extended format or HFS Plus * HPFS – High Performance File System, used on

OS/2 OS/2 (Operating System/2) is a series of computer operating systems, initially created by Microsoft and IBM under the leadership of IBM software designer Ed Iacobucci. As a result of a feud between the two companies over how to position OS/2 ...

* HTFS – High Throughput Filesystem, used on SCO OpenServer * ISO 9660 – Used on CD-ROM and

DVD-ROM The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any k ...

discs ( Rock Ridge and Joliet are extensions to this) * JFS – IBM

Journaling file system A journaling file system is a file system that keeps track of changes not yet committed to the file system's main part by recording the goal of such changes in a data structure known as a " journal", which is usually a circular log. In the ev ...

, provided in

, and AIX. Supports extents. * LFS – 4.4BSD implementation of a log-structured file system * MFS – Macintosh File System, used on early Classic Mac OS systems. Succeeded by Hierarchical File System (HFS). * Next3 – A form of ext3 with snapshots support. * MFS – TiVo's Media File System, a proprietary fault tolerant format used on TiVo hard drives for real time recording from live TV. * Minix file system – Used on Minix systems * NILFS – Linux implementation of a log-structured file system * NTFS – (New Technology File System) Used on

Microsoft Microsoft Corporation is an American multinational corporation, multinational technology company, technology corporation producing Software, computer software, consumer electronics, personal computers, and related services headquartered at th ...

Windows NT Windows NT is a proprietary graphical operating system produced by Microsoft, the first version of which was released on July 27, 1993. It is a processor-independent, multiprocessing and multi-user operating system. The first version of Wi ...

-based operating systems *

NeXT Next may refer to: Arts and entertainment Film * ''Next'' (1990 film), an animated short about William Shakespeare * ''Next'' (2007 film), a sci-fi film starring Nicolas Cage * '' Next: A Primer on Urban Painting'', a 2005 documentary film Lit ...

- NeXTstation and NeXTcube file system *

NetWare File System In computing, a NetWare File System (NWFS) is a file system based on a heavily modified version of FAT. It was used in the Novell NetWare operating system. It is the default and only file system for all volumes in versions 2.x through 4.x, and th ...

– The original NetWare 2.x–5.x file system, used optionally by later versions. * NSS – Novell Storage Services. This is a new 64-bit

journaling file system A journaling file system is a file system that keeps track of changes not yet committed to the file system's main part by recording the goal of such changes in a data structure known as a " journal", which is usually a circular log. In the ev ...

using a balanced tree algorithm. Used in NetWare versions 5.0-up and recently ported to

. * OneFS – One File System. This is a fully journaled, distributed file system used by Isilon. OneFS uses FlexProtect and Reed–Solomon encodings to support up to four simultaneous disk failures. * OFS – Old File System, on Amiga. Good for floppies, but fairly useless on hard drives. * OS-9 file system * PFS – and PFS2, PFS3, etc. Technically interesting file system available for the

, performs very well under a lot of circumstances. Very simple and elegant. * ProDOS – Operating system and file system successor to DOS 3.x, for use on Apple's computers prior to the Macintosh & Lisa computers, the Apple series, including the IIgs * Qnx4fs – File system that is used in QNX version 4 and 6. * ReFS (Resilient File System) – New file system by

that is built on the foundations of NTFS (but cannot boot, has a default cluster size of 64 KB and does not support compression) and is intended to be used with the Windows Server 2012 operating system. * ReiserFS – File system that uses journaling * Reiser4 – File system that uses journaling, newest version of ReiserFS *

Reliance Reliance may refer to: Companies * Reliance Controls, an American electrical products company founded in 1909 in Wisconsin * Reliance Home Comfort, a Canadian water heater rental and HVAC service company * Reliance Industries, an Indian co ...

– Datalight's transactional file system for high reliability applications *

Reliance Nitro Datalight was a privately held software company specializing in power failsafe and high performance software for preserving data integrity in embedded systems. The company was founded in 1983 by Roy Sherrill, and is headquartered in Bothell, Wash ...

– Tree-based transactional file system developed for high-performance embedded systems, from Datalight * RFS – Native filesystem for RTEMS *

SkyFS SkyOS (''Sky Operating System'') is a discontinued prototype commercial, proprietary, graphical desktop operating system written for the x86 computer architecture. As of January 30, 2009 development was halted with no plans to resume its developm ...

– Developed for SkyOS to replace BFS as the operating system's main file system. It is based on BFS, but contains many new features. * SFS – Smart File System,

available for the Amiga platforms. *

Soup (Apple) Soup is the file system for the Apple Newton platform, based on a shallow database system. The Newton considers its internal storage, and each inserted card, as a separate "store" (a volume). Any store may have either read/write "soups" (databases ...

– the "file system" for Apple Newton Platform, structured as a shallow database * Tux3 – An experimental versioning file system intended as a replacement for ext3 * UDF – Packet-based file system for WORM/RW media such as CD-RW and DVD, now supports hard drives and flash memory as well. * UFS – Unix File System, used on Solaris and older BSD systems * UFS2 – Unix File System, used on newer BSD systems * VxFS Veritas file system, first commercial

;

HP-UX HP-UX (from "Hewlett Packard Unix") is Hewlett Packard Enterprise's proprietary implementation of the Unix operating system, based on Unix System V (initially System III) and first released in 1984. Current versions support HPE Integrit ...

, Solaris,

, AIX, UnixWare *

VTOC In the IBM System/360Including the successors S/370 through z/Architecture storage architecture, the Volume Table of Contents (VTOC), is a data structure that provides a way of locating the data sets that reside on a particular DASD volume. With ...

(Volume Table Of Contents) - Data structure on IBM mainframe direct-access storage devices (DASD) such as disk drives that provides a way of locating the data sets that reside on the DASD volume. * XFS – Used on SGI IRIX and

systems * zFS – z/OS File System; not to be confused with other file systems named zFS or ZFS. * zFS - an IBM research project to develop a distributed, decentralized file system; not to be confused with other file systems named zFS or ZFS. * ZFS a combined file system and logical volume manager designed by

Sun Microsystems Sun Microsystems, Inc. (Sun for short) was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, ...

File systems with built-in fault-tolerance

These file systems have built-in checksumming and either mirroring or parity for extra redundancy on one or several block devices: * Bcachefs – It's not yet upstream, full data and metadata checksumming,

bcache bcache (abbreviated from ''block cache'') is a cache in the Linux kernel's block layer, which is used for accessing secondary storage devices. It allows one or more fast storage devices, such as flash-based solid-state drives (SSDs), to act a ...

is the bottom half of the filesystem. *

– A file system based on B-Trees, initially designed at

Oracle Corporation Oracle Corporation is an American multinational computer technology corporation headquartered in Austin, Texas. In 2020, Oracle was the third-largest software company in the world by revenue and market capitalization. The company sells da ...

. * HAMMER and HAMMER2 –

's primary filesystems, created by Matt Dillon. * NOVA – The "non-volatile memory accelerated" file system for persistent main memory. * ReFS (Resilient File System) – A file system by

with built-in resiliency features. *

– A transactional file system with CRCs, created by Datalight. *

– A tree-based transactional file system with CRCs, developed for high performance and reliability in embedded systems, from Datalight. * WekaFS – a shared parallel filesystem that delivers extreme performance at any scale and is optimized for NVMe and the hybrid cloud. * ZFS – Has checksums for all data; important metadata is always redundant, additional redundancy levels are user-configurable;

and transactional writing ensure metadata consistency; corrupted data can be automatically repaired if a redundant copy is available. Created by

for use on Solaris 10 and

OpenSolaris OpenSolaris () is a discontinued open-source computer operating system based on Solaris and created by Sun Microsystems. It was also, perhaps confusingly, the name of a project initiated by Sun to build a developer and user community around t ...

, ported to FreeBSD 7.0,

NetBSD NetBSD is a free and open-source Unix operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is a ...

(as of August 2009),

and to FUSE (not to be confused with the two zFSes from IBM)

File systems optimized for flash memory, solid state media

Solid state media, such as

flash memory Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both u ...

, are similar to disks in their interfaces, but have different problems. At low level, they require special handling such as

wear leveling Wear leveling (also written as wear levelling) is a technique Wear leveling techniques for flash memory systems. for prolonging the service life of some kinds of erasable computer storage media, such as flash memory, which is used in solid-state d ...

and different

error detection and correction In information theory and coding theory with applications in computer science and telecommunication, error detection and correction (EDAC) or error control are techniques that enable reliable delivery of digital data over unreliable comm ...

algorithms. Typically a device such as a

solid-state drive A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It i ...

handles such operations internally and therefore a regular file system can be used. However, for certain specialized installations (embedded systems, industrial applications) a file system optimized for plain flash memory is advantageous. * APFS – Apple File System is a next-generation file system for Apple products. *

CHFS CHFS is a file system developed at the Department of Software Engineering, University of Szeged, Hungary. It was the first open source flash memory-specific file system written for the NetBSD operating system. Intended usage is over raw flash de ...

– a

filesystem for

embedded system An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' ...

s optimised for raw flash media. * exFAT –

proprietary system intended for flash cards (see also XCFiles, an exFAT implementation for Wind River

VxWorks VxWorks is a real-time operating system (or RTOS) developed as proprietary software by Wind River Systems, a wholly-owned subsidiary of Aptiv. First released in 1987, VxWorks is designed for use in embedded systems requiring real-time, dete ...

and other embedded operating systems). * ExtremeFFS – internal filesystem for SSDs. * F2FS – Flash-Friendly File System. An open source Linux file system introduced by

Samsung The Samsung Group (or simply Samsung) ( ko, 삼성 ) is a South Korean multinational manufacturing conglomerate headquartered in Samsung Town, Seoul, South Korea. It comprises numerous affiliated businesses, most of them united under the ...

in 2012. * FFS2 (presumably preceded by FFS1), one of the earliest flash file systems. Developed and patented by

in the early 1990s. * JFFS – original log structured Linux file system for NOR flash media. * JFFS2 – successor of JFFS, for NAND and NOR flash. *

LSFS A log-structured filesystem is a file system in which data and metadata are written sequentially to a circular buffer, called a log. The design was first proposed in 1988 by John K. Ousterhout and Fred Douglis and first implemented in 1992 by O ...

– a Log-structured file system with writable snapshots and inline data deduplication created by StarWind Software. Uses DRAM and flash to cache spinning disks. *

LogFS LogFS is a Linux log-structured and scalable flash file system, intended for use on large devices of flash memory. It is written by Jörn Engel and in part sponsored by the CE Linux Forum. LogFS was introduced in the mainline Linux kernel in v ...

– intended to replace JFFS2, better scalability. No longer under active development. * NILFS – a log-structured file system for Linux with continuous snapshots. * Non-Volatile File System – the system for

introduced by Palm, Inc. * NOVA – the "non-volatile memory accelerated" file system for persistent main memory. * OneFS – a filesystem utilized by Isilon. It supports selective placement of meta-data directly onto flash SSD. * Segger Microcontroller Systems emFile – filesystem for deeply embedded applications which supports both NAND and NOR flash. Wear leveling, fast read and write, and very low RAM usage. * SPIFFS – SPI Flash File System, a wear-leveling filesystem intended for small NOR flash devices. *

TFAT Transaction-Safe FAT File System (TFAT) and Transaction-Safe Extended FAT File System (TexFAT) refer to two file systems used in Microsoft products to provide transaction-safety for data stored on a disk. The goal is to reduce the risk of data loss ...

– a transactional version of the FAT filesystem. *

TrueFFS A flash memory controller (or flash controller) manages data stored on flash memory (usually NAND flash) and communicates with a computer or electronic device. Flash memory controllers can be designed for operating in low duty-cycle environments l ...

– internal file system for SSDs, implementing error correction, bad block re-mapping and wear-leveling. * UBIFS – successor of JFFS2, optimized to utilize NAND and NOR flash. * Write Anywhere File Layout (WAFL) – an internal file system utilized by NetApp within their DataONTAP OS, originally optimized to use non-volatile DRAM. WAFL uses RAID-DP to protect against multiple disk failures and NVRAM for transaction log replays. * YAFFS – a log-structured file system designed for NAND flash, but also used with NOR flash.
LittleFS
– a little fail-safe filesystem designed for microcontrollers. * JesFS – Jo's embedded serial FileSystem. A very small footprint and robust filesystem, designed for very small microcontroller (16/32 bit). Open Source and licensed under GPL v3.

Record-oriented file systems

In record-oriented file systems files are stored as a collection of records. They are typically associated with mainframe and

minicomputer A minicomputer, or colloquially mini, is a class of smaller general purpose computers that developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, ...

operating systems. Programs read and write whole records, rather than bytes or arbitrary byte ranges, and can seek to a record boundary but not within records. The more sophisticated record-oriented file systems have more in common with simple

database In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spa ...

s than with other file systems. * CMS file system – The native file system of the Conversational Monitor System component of VM/370 * Files-11 – early versions were record-oriented; support for "streams" was added later * Michigan Terminal System (MTS) – provides "line files" where record lengths and line numbers are associated as metadata with each record in the file, lines can be added, replaced, updated with the same or different length records, and deleted anywhere in the file without the need to read and rewrite the entire file. * OS4000 for GEC's OS4000 operating system, on the GEC 4000 series minicomputers * A FAT12 and FAT16 (and

) extension to support database-like file types ''random file'', ''direct file'', ''keyed file'' and ''sequential file'' in Digital Research FlexOS, IBM 4680 OS and Toshiba 4690 OS.IBM. ''4690 OS Programming Guide Version 5.2'', IBM document SC30-4137-01, 2007-12-06 ( tp://ftp.software.ibm.com/software/retail/pubs/sw/opsys/4690/ver5r2/bsi1_PG_mst.pdf. The record size is stored on a file-by-file basis in special entries in the directory table.Caldera (1997). ''Caldera OpenDOS Machine Readable Source Kit 7.01''. The FDOS.EQU file in the machine readable source kit has equates for the corresponding directory entries. * Sequential access methods for IBM's z/OS and

z/VSE VSEn (''Virtual Storage Extended'') is an operating system for IBM mainframe computers, the latest one in the DOS/360 lineage, which originated in 1965. DOS/VSE was introduced in 1979 as a successor to DOS/VS; in turn, DOS/VSE was succeeded by ...

mainframe operating systems: Basic Sequential Access Method (BSAM), Basic Partitioned Access Method (BPAM) and Queued Sequential Access Method (QSAM); see Access methods and Data set (IBM mainframe) for more examples * Pick Operating System – A record-oriented filesystem and database that uses hash-coding to store data. * Shared File System (SFS) for IBM's VM * Virtual Storage Access Method (VSAM) for IBM's z/OS and

mainframe operating systems

Shared-disk file systems

Shared-disk file systems (also called ''shared-storage file systems'', SAN file system, Clustered file system or even ''cluster file systems'') are primarily used in a storage area network where all nodes directly access the

block storage In computing (specifically data transmission and data storage), a block, sometimes called a physical record, is a sequence of bytes or bits, usually containing some whole number of records, having a maximum length; a ''block size''. Data t ...

where the file system is located. This makes it possible for nodes to fail without affecting access to the file system from the other nodes. Shared-disk file systems are normally used in a high-availability cluster together with storage on hardware RAID. Shared-disk file systems normally do not scale over 64 or 128 nodes. Shared-disk file systems may be

symmetric Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definit ...

where metadata is distributed among the nodes or

asymmetric Asymmetric may refer to: *Asymmetry in geometry, chemistry, and physics Computing * Asymmetric cryptography, in public-key cryptography *Asymmetric digital subscriber line, Internet connectivity * Asymmetric multiprocessing, in computer architect ...

with centralized metadata servers. * CXFS (Clustered XFS) from Silicon Graphics (SGI). Available for Linux, Mac, Windows, Solaris, AIX and IRIX,. Asymmetric. *

Dell Fluid File System Dell Fluid File System, or FluidFS, is a shared-disk filesystem made by Dell that provides distributed file systems to clients. Customers buy an appliance: a combination of purpose-built network-attached storage (NAS) controllers with integrat ...

(formerly ExaFS)

proprietary software Proprietary software is computer software, software that is deemed within the free and open-source software to be non-free because its creator, publisher, or other rightsholder or rightsholder partner exercises a legal monopoly afforded by modern ...

sold by

Dell Dell is an American based technology company. It develops, sells, repairs, and supports computers and related products and services. Dell is owned by its parent company, Dell Technologies. Dell sells personal computers (PCs), servers, data ...

. Shared-disk system sold as an appliance providing distributed file systems to clients. Running on Intel based hardware serving NFS v2/v3, SMB/CIFS and AFP to

Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for ...

macOS macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac (computer), Mac computers. Within the market of ...

and other

UNIX Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

clients. * Blue Whale Clustered file system (BWFS) from Zhongke Blue Whale. Asymmetric. Available for Microsoft Windows,

, and

. * SAN File System (SFS) from DataPlow. Available for Windows, Linux, Solaris, and macOS. Symmetric and Asymmetric. * EMC Celerra HighRoad from EMC. Available for Linux, AIX, HP-UX, IRIX, Solaris and Windows. Asymmetric. * Files-11 on VMSclusters, released by DEC in 1983, now from HP. Symmetric. * GFS2 (''Global File System'') from Red Hat. Available for Linux under GPL. Symmetric ( GDLM) or Asymmetric ( GULM). * IBM General Parallel File System (GPFS) Windows, Linux, AIX . Parallel * Nasan Clustered File System from DataPlow. Available for Linux and Solaris. Asymmetric. * Oracle ACFS from

. Available for Linux (

Red Hat Enterprise Linux Red Hat Enterprise Linux (RHEL) is a Commercial software, commercial Open-source software, open-source Linux distribution developed by Red Hat for the commerce, commercial market. Red Hat Enterprise Linux is released in server versions for x86-6 ...

5 and Oracle Enterprise Linux 5 only). Symmetric. * OCFS2 (''Oracle Cluster File System'') from

. Available for Linux under GPL. Symmetric. * QFS from

. Available for Linux (client only) and Solaris (metadata server and client). Asymmetric. * ScoutFS from Versity. Available for Linux under the GPL. Symmetric. * StorNext File System from Quantum. Asymmetric. Available for AIX,

, IRIX,

, Solaris and

. Interoperable with

Xsan Xsan () is Apple Inc.'s storage area network (SAN) or clustered file system for macOS. Xsan enables multiple Mac desktop and Xserve systems to access shared block storage over a Fibre Channel network. With the Xsan file system installed, these ...

. Formerly known as CVFS. * Veritas Storage Foundation from

Symantec Symantec may refer to: *An American consumer software company now known as Gen Digital Inc. *A brand of enterprise security software purchased by Broadcom Inc. Broadcom Inc. is an American designer, developer, manufacturer and global supplier ...

. Available for AIX, HP-UX, Linux and Solaris. Asymmetric. *

from Apple Inc. Available for macOS. Asymmetric. Interoperable with StorNext File System. * VMFS from VMware/ EMC Corporation. Available for VMware ESX Server. Symmetric.

Distributed file systems

Distributed file systems are also called network file systems. Many implementations have been made, they are location dependent and they have access control lists (ACLs), unless otherwise stated below. * 9P, the Plan 9 from Bell Labs and Inferno distributed file system protocol. One implementation is v9fs. No ACLs. * Amazon S3 * Andrew File System (AFS) is scalable and location independent, has a heavy client cache and uses Kerberos for authentication. Implementations include the original from IBM (earlier Transarc), Arla and OpenAFS. * Avere Systems has AvereOS that creates a NAS protocol file system in object storage. * DCE Distributed File System ( DCE/DFS) from IBM (earlier Transarc) is similar to AFS and focus on full

POSIX The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines both the system- and user-level application programming inte ...

file system semantics and

high availability High availability (HA) is a characteristic of a system which aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period. Modernization has resulted in an increased reliance on these systems. F ...

. Available for AIX and Solaris under a

license. *

File Access Listener DECnet is a suite of network protocols created by Digital Equipment Corporation. Originally released in 1975 in order to connect two PDP-11 minicomputers, it evolved into one of the first peer-to-peer network architectures, thus transforming DEC ...

(FAL) is an implementation of the Data Access Protocol (DAP) which is part of the DECnet suite of network protocols created by

. *

Magma Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natura ...

, developed by Tx0. * MapR FS is a distributed high-performance file system that exhibits file, table and messaging APIs. * Microsoft Office Groove shared workspace, used for DoHyki * NetWare Core Protocol (NCP) from

Novell Novell, Inc. was an American software and services company headquartered in Provo, Utah, that existed from 1980 until 2014. Its most significant product was the multi- platform network operating system known as Novell NetWare. Under the l ...

is used in networks based on NetWare. *

Network File System Network File System (NFS) is a distributed file system protocol originally developed by Sun Microsystems (Sun) in 1984, allowing a user on a client computer to access files over a computer network much like local storage is accessed. NFS, li ...

(NFS) originally from

is the standard in UNIX-based networks. NFS may use Kerberos authentication and a client cache. * OS4000 Linked-OS provides distributed filesystem across OS4000 systems. * Self-certifying File System (SFS), a global network file system designed to securely allow access to file systems across separate administrative domains. * Server Message Block (SMB) originally from IBM (but the most common version is modified heavily by

) is the standard in Windows-based networks. SMB is also known as ''Common Internet File System (CIFS)''. SMB may use Kerberos authentication.

Distributed fault-tolerant file systems

Distributed fault-tolerant replication of data between nodes (between servers or servers/clients) for

and offline (disconnected) operation. * Coda from

Carnegie Mellon University Carnegie Mellon University (CMU) is a private research university in Pittsburgh, Pennsylvania. One of its predecessors was established in 1900 by Andrew Carnegie as the Carnegie Technical Schools; it became the Carnegie Institute of Technology ...

focuses on bandwidth-adaptive operation (including disconnected operation) using a client-side cache for mobile computing. It is a descendant of AFS-2. It is available for

under the GPL. * Distributed File System (Dfs) from

focuses on location transparency and

. Available for

under a

license. * HAMMER and HAMMER2 –

's filesystems for clustered storage, created by Matt Dillon. *

InterMezzo In music, an intermezzo (, , plural form: intermezzi), in the most general sense, is a composition which fits between other musical or dramatic entities, such as acts of a play or movements of a larger musical work. In music history, the term ha ...

from

Cluster File Systems Lustre is a type of parallel distributed file system, generally used for large-scale cluster computing. The name Lustre is a portmanteau word derived from Linux and cluster. Lustre file system software is available under the GNU General Public ...

uses synchronization over

HTTP The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, ...

. Available for

under GPL but no longer in development since the developers are working on Lustre. * LizardFS a networking, distributed file system based on MooseFS * Moose File System (MooseFS) is a networking, distributed file system. It spreads data over several physical locations (servers), which are visible to a user as one resource. Works on Linux, FreeBSD, NetBSD, OpenSolaris and macOS. Master server and chunkservers can also run on Solaris and Windows with Cygwin. *

Scality Scality is a company based in San Francisco, California that develops software-defined object storage. RING is the company's commercial product. Scality RING software deploys on industry-standard servers to store objects and files. Scality also ...

is a distributed fault-tolerant filesystem. * Tahoe-LAFS is an open source secure, decentralized, fault-tolerant filesystem utilizing encryption as the basis for a least-authority replicated design. * A FAT12 and FAT16 (and

) extension to support automatic file distribution across nodes with extra attributes like ''local'', ''mirror on update'', ''mirror on close'', ''compound on update'', ''compound on close'' in IBM 4680 OS and Toshiba 4690 OS. The distribution attributes are stored on a file-by-file basis in special entries in the directory table.IBM (2003). ''Information about 4690 OS unique file distribution attributes'', IBM document R1001487, 2003-07-30. (): " ..file types are stored in the "Reserved bits" portion of the PC-DOS file directory structure ..only 4690 respects and preserves these attributes. Various non-4690 operating systems take different actions if these bits are turned on ..when copying from a diskette created on a 4690 system. ..PC-DOS and Windows 2000 Professional will copy the file without error and zero the bits. OS/2 ..1.2 ..will refuse to copy the file unless ..first run CHKDSK /F on the file. After ..CHKDSK, it will copy the file and zero the bits. ..when ..copy ..back to the 4690 system, ..file will copy as a local file."IBM. ''4690 save and restore file distribution attributes''. IBM document R1000622, 2010-08-31 ().

Distributed parallel file systems

Distributed parallel file systems stripe data over multiple servers for high performance. They are normally used in high-performance computing (HPC). Some of the distributed parallel file systems use an

object storage device Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an a ...

(OSD) (in Lustre called OST) for chunks of data together with centralized metadata servers. * Lustre is an open-source high-performance distributed parallel file system for Linux, used on many of the largest computers in the world. *

Parallel Virtual File System The Parallel Virtual File System (PVFS) is an open-source parallel file system. A parallel file system is a type of distributed file system that distributes file data across multiple servers and provides for concurrent access by multiple tasks of ...

(PVFS, PVFS2,

OrangeFS OrangeFS is an open-source parallel file system, the next generation of Parallel Virtual File System (PVFS). A parallel file system is a type of distributed file system that distributes file data across multiple servers and provides for concurr ...

). Developed to store virtual system images, with a focus on non-shared writing optimizations. Available for

under GPL.

Distributed parallel fault-tolerant file systems

Distributed file systems, which also are parallel and fault tolerant, stripe and replicate data over multiple servers for high performance and to maintain data integrity. Even if a server fails no data is lost. The file systems are used in both high-performance computing (HPC) and high-availability clusters. All file systems listed here focus on

, scalability and high performance unless otherwise stated below. In development: * zFS from IBM (not to be confused with ZFS from

or the zFS file system provided with IBM's z/OS operating system) focus on

cooperative cache A cooperative (also known as co-operative, co-op, or coop) is "an autonomy, autonomous association of persons united voluntarily to meet their common economic, social and cultural needs and aspirations through a jointly owned and democratical ...

and distributed transactions and uses

s. Under development and not freely available. * HAMMER/ANVIL by Matt Dillon *

PNFS Network File System (NFS) is a distributed file system protocol originally developed by Sun Microsystems (Sun) in 1984, allowing a user on a client computer to access files over a computer network much like local storage is accessed. NFS, like ...

(Parallel NFS) – Clients available for

and

and back-ends from NetApp,

Panasas Panasas is a data storage company that creates network-attached storage for technical computing environments. History Panasas is a computer data storage product company and is headquartered in San Jose, California. Panasas received seed fundi ...

, EMC Highroad and IBM

GPFS GPFS (General Parallel File System, brand name IBM Spectrum Scale) is high-performance clustered file system software developed by IBM. It can be deployed in shared-disk or shared-nothing distributed parallel modes, or a combination of these. I ...

* Coherent Remote File System (CRFS) – requires

* Parallel Optimized Host Message Exchange Layered File System (POHMELFS) and Distributed STorage (DST). POSIX compliant, added to Linux kernel 2.6.30

Peer-to-peer file systems

Some of these may be called cooperative storage cloud. * Cleversafe uses Cauchy Reed–Solomon

information dispersal algorithms Information is an abstract concept that refers to that which has the power to inform. At the most fundamental level information pertains to the interpretation of that which may be sensed. Any natural process that is not completely random ...

to separate data into unrecognizable slices and distribute them, via secure Internet connections, to multiple storage locations. *

is a distributed filesystem using the

Chord Chord may refer to: * Chord (music), an aggregate of musical pitches sounded simultaneously ** Guitar chord a chord played on a guitar, which has a particular tuning * Chord (geometry), a line segment joining two points on a curve * Chord ( ...

peer-to-peer protocol. * IPFS InterPlanetary File System is p2p, worldwide distributed content-addressable, file-system.

Special-purpose file systems

* aufs an enhanced version of UnionFS stackable unification file system * AXFS (small footprint compressed read-only, with XIP) * Barracuda WebDAV plug-in. Secure Network File Server for embedded devices. * Boot File System is used on UnixWare to store files necessary for its boot process. *

cdfs CDfs is a virtual file system for Unix-like operating systems; it provides access to data and audio tracks on Compact Discs. When the CDfs driver mounts a Compact Disc, it represents each track as a file. This is consistent with the Unix conve ...

(reading and writing of CDs) * Compact Disc File System (reading and writing of CDs; experimental) *

cfs CFS is an acronym for: Organizations * Canadian Federation of Students * Canadian Forest Service * Center for Financial Studies, a research institute affiliated with Goethe University Frankfurt * Center for Subjectivity Research, a research insti ...

(caching) * Cramfs (small footprint compressed read-only) *

Davfs2 In computer networking davfs2 is a Linux tool for connecting to WebDAV shares as though they were local disks. It is an open-source GPL-licensed file system for mounting WebDAV servers. It uses the FUSE file system API to communicate with the kern ...

( WebDAV) * Freenet – Decentralized, censorship-resistant * FTPFS (FTP access) * GmailFS (Google Mail File System) * GridFS – GridFS is a specification for storing and retrieving files that exceed the BSON-document size limit of 16 MB for MongoDB. * lnfs (long names) *

LTFS The Linear Tape File System (LTFS) is a file system that allows files stored on magnetic tape to be accessed in a similar fashion to those on disk or removable flash drives. It requires both a specific format of data on the tape media and software ...

(Linear Tape File System for LTO and Enterprise tape) * MVFS – MultiVersion File System, proprietary, used by

Rational ClearCase Rational ClearCase is a family of computer software tools that supports software configuration management (SCM) of source code and other software development assets. It also supports design-data management of electronic design artifacts, thus e ...

.
Nexfs
Combines Block, File, Object and Cloud storage into a single pool of auto-tiering POSIX compatible storage. *

romfs In computing, romfs (ROM filesystem) is an extremely simple file system lacking many features, intended for burning important files onto an EEPROM EEPROM (also called E2PROM) stands for electrically erasable programmable read-only memo ...

* SquashFS (compressed read-only) * UMSDOS, UVFAT – FAT file systems extended to store permissions and metadata (and in the case of UVFAT, VFAT long file names), used for Linux * UnionFS – stackable unification file system, which can appear to merge the contents of several directories (branches), while keeping their physical content separate * Venti – Plan 9 de-duplicated storage used by

Pseudo file systems

* devfs – a virtual file system in Unix-like operating systems for managing device nodes on-the-fly *

procfs The proc filesystem (procfs) is a special filesystem in Unix-like operating systems that presents information about processes and other system information in a hierarchical file-like structure, providing a more convenient and standardized meth ...

– a pseudo-file system, used to access kernel information about processes *

tmpfs tmpfs (short for Temporary File System) is a temporary file storage paradigm implemented in many Unix-like operating systems. It is intended to appear as a mounted file system, but data is stored in volatile memory instead of a persistent stora ...

– in-memory temporary file system (on Unix-like platforms) *

sysfs sysfs is a pseudo file system provided by the Linux kernel that exports information about various kernel subsystems, hardware devices, and associated device drivers from the kernel's device model to user space through virtual files. In addit ...

– a virtual file system in

holding information about buses, devices, firmware, filesystems, etc. * debugfs – a virtual file system in

for accessing and controlling kernel debugging * configfs – a writable file system used to configure various kernel components of

* sysctlfs – allow accessing sysctl nodes via a file system; available on

via PUFFS, FreeBSD kernel via a 3rd-party module, and

as a part of Linux procfs. * kernfs – a file system found on some BSD systems (notably

) that provides access to some kernel state variables; similar to sysctlfs, Linux procfs and Linux sysfs. * wikifs – a server application for

Plan 9 Plan 9 or Plan Nine may refer to: Music * Plan 9 (band), a psychedelic rock band from Rhode Island * ''Plan 9'', an album by Big Guitars From Memphis with Rick Lindy * "Plan 9", a song on the 1993 album ''Gorgeous'' by electronica band 808 Stat ...

's virtual,

wiki A wiki ( ) is an online hypertext publication collaboratively edited and managed by its own audience, using a web browser. A typical wiki contains multiple pages for the subjects or scope of the project, and could be either open to the pu ...

, file system

Encrypted file systems

* eCryptfs – a stacked cryptographic file system in the Linux kernel since 2.6.19 * Secure Shell File System (SSHFS) – locally mount a remote directory on a server using only a

secure shell The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. Its most notable applications are remote login and command-line execution. SSH applications are based ...

login. * EncFS, GPL Encrypted file system in user-space * Rubberhose filesystem * EFS – an encrypted file system for Microsoft Windows systems and AIX. An extension of NTFS * ZFS, with encryption support.

File system interfaces

These are not really file systems; they allow access to file systems from an operating system standpoint. * FUSE (file system in userspace, like LUFS but better maintained) * LUFS (Linux userland file system – seems to be abandoned in favour of FUSE) * PUFFS (Userspace filesystem for NetBSD, including a compatibility layer called librefuse for porting existing FUSE-based applications) * VFS Virtual Filesystem

References

External links

File Systems
{{DEFAULTSORT:List Of File Systems *

File systems In computing, file system or filesystem (often abbreviated to fs) is a method and data structure that the operating system uses to control how data is stored and retrieved. Without a file system, data placed in a storage medium would be one larg ...