List of file systems
Encyclopedia
The following lists identify, characterize and link to more thorough information on computer
file system
s.
Many older operating system
s support only their one "native" file system, which does not bear any name apart from the name of the operating system itself.
, are similar to disks in their interfaces, but have different problems. While practically eliminating seek times, they require special handling such as wear leveling
and different error detection and correction
algorithms.
files are stored as a collection of records
. They are typically associated with mainframe
and minicomputer
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
s than with other file systems.
or even cluster file systems) are primarily used in a storage area network
where all nodes directly access the block storage 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 where metadata
is distributed among the nodes or asymmetric
with centralized metadata
servers.
Parallel filesystem - file systems with support for parallel applications, all nodes may be accessing the same files at the same time, concurrently reading and writing. Data for a single file is striped across multiple storage nodes to provide scalable performance to individual files. Examples of this include: Panasas ActiveScale, Lustre, GPFS and Sistina. NFSv4.1 will feature an extension to the NFS standard that supports parallel IO.
s 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.
and offline (disconnected) operation.
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 object storage device
(OSD) (In Lustre called OST) for chunks of data together with centralized metadata
servers.
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 cluster
s.
All file systems listed here focus on high availability
, scalability
and high performance unless otherwise stated below.
In development:
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
file system
File system
A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...
s.
Many older operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
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.- ADFSAdvanced Disc Filing SystemThe Advanced Disc Filing System is a computing file system particular to the Acorn computer range and RISC OS based successors. Initially based on the rare Acorn Winchester Filing System, it was renamed to the Advanced Disc Filing System when support for floppy discs was added and on later 32 bit...
– Acorn's Advanced Disc filing system, successor to DFSDisc Filing SystemThe Disc Filing System is a computer file system developed by Acorn Computers Ltd, and introduced in 1982 for the Acorn BBC Microcomputer. It was shipped as a ROM to be inserted onto the BBC Micro's motherboard. It has an extremely limited design, and uses a flat directory structure...
. - AdvFSAdvFSAdvFS, also known as Tru64 UNIX Advanced File System, is a file system developed in the late 1980s to mid 1990s by Digital Equipment Corporation for their OSF/1 version of the Unix operating system...
- Advanced File System, designed by Digital Equipment CorporationDigital Equipment CorporationDigital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
for their Digital UNIX (now Tru64 UNIXTru64 UNIXTru64 UNIX is a 64-bit UNIX operating system for the Alpha instruction set architecture , currently owned by Hewlett-Packard . Previously, Tru64 UNIX was a product of Compaq, and before that, Digital Equipment Corporation , where it was known as Digital UNIX .As its original name suggests, Tru64...
) operating system. - AFS (Not to be confused with Andrew File System, below) – Acer Fast Filesystem, used on SCO OpenServerSCO OpenServerSCO OpenServer, previously SCO UNIX and SCO Open Desktop , is, misleadingly, a closed source version of the Unix computer operating system developed by Santa Cruz Operation and now maintained by the SCO Group....
- AFS - Ami File Safe, a commercial filesystem shipped on Amiga in the 1990s (AFS is structure compatible with PFSProfessional File SystemThe Professional File System is a filesystem originally developed commercially for the Amiga, it is now distributed on Aminet with a 4-clause BSD license. PFS tends to perform very well, due to the simplicity of design. Compatible successor of Ami-FileSafe....
) - AthFSAtheOS File SystemThe AtheOS file system was originally used in the AtheOS operating system, and is now a part of the Syllable operating system. AFS started with exactly the same data structures as the Be File System, BFS, and extended its feature set in many ways. As such, AFS is a 64-bit journaled file system...
- AtheOSAtheOSAtheOS was a free and open source operating system for x86-based computers. It was initially intended as an AmigaOS clone, but that objective was later abandoned...
File System, a 64-bit journaledJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
filesystem now used by Syllable. Also called AFS - BFSBe File SystemThe Be File System is the native file system for the BeOS....
– the Be File System used on BeOSBeOSBeOS is an operating system for personal computers which began development by Be Inc. in 1991. It was first written to run on BeBox hardware. BeOS was optimized for digital media work and was written to take advantage of modern hardware facilities such as symmetric multiprocessing by utilizing...
, occasionally misnamed as BeFS. Open source implementation called OpenBFS is used by the HaikuHaiku (operating system)Haiku is a free and open source operating system compatible with BeOS. Its development began in 2001, and the operating system became self-hosting in 2008, with the first alpha release in September 2009, the second in May 2010 and the third in June 2011....
operating system. - BtrfsBtrfsBtrfs is a GPL-licensed copy-on-write file system for Linux.Development began at Oracle Corporation in 2007....
- is a copy-on-writeCopy-on-writeCopy-on-write is an optimization strategy used in computer programming. The fundamental idea is that if multiple callers ask for resources which are initially indistinguishable, they can all be given pointers to the same resource...
file system for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
announced by OracleOracle CorporationOracle Corporation is an American multinational computer technology corporation that specializes in developing and marketing hardware systems and enterprise software products – particularly database management systems...
in 2007 and published under the GNU General Public LicenseGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
(GPL). - CBMFS – The filesystem used on most Commodore 64Commodore 64The Commodore 64 is an 8-bit home computer introduced by Commodore International in January 1982.Volume production started in the spring of 1982, with machines being released on to the market in August at a price of US$595...
-compatible floppy drives including the venerable 1541Commodore 1541The Commodore 1541 , made by Commodore International, was the best-known floppy disk drive for the Commodore 64 home computer. The 1541 was a single-sided 170 kilobyte drive for 5¼" disks...
. - CMDFS – A filesystem extension added to CBMFS by Creative Micro DesignsCreative Micro DesignsCreative Micro Designs is a computer technologies company which today sells PCs and related equipment, but which started out in 1987 selling self-designed firmware updates and hardware for the Commodore 64 and C128 8-bit home/personal computers....
, for use in their 3.5 inch floppy drives, RAM disks, and hard drive controllers. - CP/MCP/MCP/M was a mass-market operating system created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc...
file system — Native filesystem used in the CP/M (Control Program for Microcomputers) operating system which was first released in the late 1970s. - DDFS – Data Domain File System, the data deduplicationData deduplicationIn computing, data deduplication is a specialized data compression technique for eliminating coarse-grained redundant data. The technique is used to improve storage utilization and can also be applied to network data transfers to reduce the number of bytes that must be sent across a link...
file system that ships in the Data Domain Deduplication Storage Systems which are an alternative to tape for storing backups and archives. - DTFS – Desktop File System, featuring file compression, used by SCO OpenServerSCO OpenServerSCO OpenServer, previously SCO UNIX and SCO Open Desktop , is, misleadingly, a closed source version of the Unix computer operating system developed by Santa Cruz Operation and now maintained by the SCO Group....
- DOS 3.xApple DOSApple DOS refers to operating systems for the Apple II series of microcomputers from late 1978 through early 1983. Apple DOS had three major releases: DOS 3.1, DOS 3.2, and DOS 3.3; each one of these three releases was followed by a second, minor "bug-fix" release, but only in the case of Apple DOS...
- Original floppy operating system and file system developed for the Apple IIApple IIThe Apple II is an 8-bit home computer, one of the first highly successful mass-produced microcomputer products, designed primarily by Steve Wozniak, manufactured by Apple Computer and introduced in 1977... - EAFS – Extended Acer Fast Filesystem, used on SCO OpenServerSCO OpenServerSCO OpenServer, previously SCO UNIX and SCO Open Desktop , is, misleadingly, a closed source version of the Unix computer operating system developed by Santa Cruz Operation and now maintained by the SCO Group....
- Extent File System (EFS) – an older block filing system under IRIXIRIXIRIX is a computer operating system developed by Silicon Graphics, Inc. to run natively on their 32- and 64-bit MIPS architecture workstations and servers. It was based on UNIX System V with BSD extensions. IRIX was the first operating system to include the XFS file system.The last major version...
. - extExtended file systemThe extended file system or ext was implemented in April 1992 as the first file system created specifically for the Linux operating system. It has metadata structure inspired by the traditional Unix File System and was designed by Rémy Card to overcome certain limitations of the Minix file...
– Extended file system, designed for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
systems - ext2Ext2The ext2 or second extended filesystem is a file system for the Linux kernel. It was initially designed by Rémy Card as a replacement for the extended file system ....
– Second extended file system, designed for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
systems. - ext3Ext3The ext3 or third extended filesystem is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian...
– A journaledJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
form of ext2. - ext4Ext4The ext4 or fourth extended filesystem is a journaling file system for Linux, developed as the successor to ext3.It was born as a series of backward compatible extensions to ext3, many of them originally developed by Cluster File Systems for the Lustre file system between 2003 and 2006, meant to...
– A follow up for ext3Ext3The ext3 or third extended filesystem is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian...
and also a journaledJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
filesystem with support for extents. - ext3cowExt3cowExt3cow or third extended filesystem with copy-on-write is an open source, versioning file system based on the ext3 file system. Versioning is implemented through block-level copy-on-write. It shares many of its performance characteristics with ext3....
– A versioning file systemVersioning file systemA versioning file system is any computer file system which allows a computer file to exist in several versions at the same time. Thus it is a form of revision control. Most common versioning file systems keep a number of old copies of the file. Some limit the number of changes per minute or per...
form of ext3. - FATFile Allocation TableFile Allocation Table is a computer file system architecture now widely used on many computer systems and most memory cards, such as those used with digital cameras. FAT file systems are commonly found on floppy disks, flash memory cards, digital cameras, and many other portable devices because of...
– File Allocation Table, used on DOSDOSDOS, short for "Disk Operating System", is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 if one includes the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.Related...
and Microsoft WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, 12-, 16- and 32-bit table depths.- VFAT – Version of Microsoft WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
FAT system with extension to allow long (up to 255 character) filenames instead of only the 8.3 filenames allowed in the original FAT. - FATX – A modified version of Microsoft WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
FAT system that is used on the original XboxXboxThe Xbox is a sixth-generation video game console manufactured by Microsoft. It was released on November 15, 2001 in North America, February 22, 2002 in Japan, and March 14, 2002 in Australia and Europe and is the predecessor to the Xbox 360. It was Microsoft's first foray into the gaming console...
console.
- VFAT – Version of Microsoft Windows
- FFS (Amiga)Amiga Fast File SystemThe Amiga Fast File System is a file system used on the Amiga personal computer. The previous Amiga filesystem upon the release of FFS became known as Amiga Old File System . OFS, while fine on floppy disk, soon proved too slow to keep up with era hard drives...
– Fast File System, used on AmigaAmigaThe Amiga is a family of personal computers that was sold by Commodore in the 1980s and 1990s. The first model was launched in 1985 as a high-end home computer and became popular for its graphical, audio and multi-tasking abilities...
systems. This FS has evolved over time. Now counts FFS1, FFS Intl, FFS DCache, FFS2. - FFS – Fast File System, used on *BSD systems
- FossilFossil (file system)Fossil is the default file system in Plan 9 from Bell Labs. It serves the network protocol 9P and runs as a user space daemon, like most Plan 9 file servers. Fossil is different from most other file systems due to its snapshot/archival feature. It can take snapshots of the entire file system on...
– Plan 9 from Bell LabsPlan 9 from Bell LabsPlan 9 from Bell Labs is a distributed operating system. It was developed primarily for research purposes as the successor to Unix by the Computing Sciences Research Center at Bell Labs between the mid-1980s and 2002...
snapshot archival file system. - Files-11Files-11Files-11, also known as on-disk structure, is the file system used by Hewlett-Packard's OpenVMS operating system, and also by the older RSX-11...
– OpenVMSOpenVMSOpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...
file system; also used on some PDP-11PDP-11The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 replaced the PDP-8 in many real-time applications, although both product lines lived in parallel for more than 10 years...
systems; supports record-orientated files - HFSHierarchical File SystemHierarchical File System is a 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...
– 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/OSZ/OSz/OS is a 64-bit operating system for mainframe computers, produced by IBM. It derives from and is the successor to OS/390, which in turn followed a string of MVS versions.Starting with earliest:*OS/VS2 Release 2 through Release 3.8... - HFS+HFS PlusHFS Plus or HFS+ is a file system developed by Apple Inc. to replace their Hierarchical File System as the primary file system used in Macintosh computers . It is also one of the formats used by the iPod digital music player...
– Updated version of Apple’s HFS, Hierarchical File System, supported on Mac OS 8.1 & above, including Mac OS X. 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/2OS/2OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
- HTFSHigh Throughput File SystemHigh Throughput File System is the journaling file system used by current versions ofSCO OpenServer. It is the successor of EAFS....
– High Throughput Filesystem, used on SCO OpenServerSCO OpenServerSCO OpenServer, previously SCO UNIX and SCO Open Desktop , is, misleadingly, a closed source version of the Unix computer operating system developed by Santa Cruz Operation and now maintained by the SCO Group.... - ISO 9660ISO 9660ISO 9660, also referred to as CDFS by some hardware and software providers, is a file system standard published by the International Organization for Standardization for optical disc media....
– Used on CD-ROMCD-ROMA CD-ROM is a pre-pressed compact disc that contains data accessible to, but not writable by, a computer for data storage and music playback. The 1985 “Yellow Book” standard developed by Sony and Philips adapted the format to hold any form of binary data....
and DVD-ROMDVDA DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
discs (Rock RidgeRock RidgeThe Rock Ridge Interchange Protocol is an extension to the ISO 9660 volume format, commonly used on CDROM and DVD media, which adds POSIX file system semantics...
and JolietJoliet (file system)Joliet is the name of an extension to the ISO 9660 file system. It has been specified and endorsed by Microsoft and has been supported by all versions of its Windows OS since Windows 95 and Windows NT...
are extensions to this) - JFS – IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
Journaling file systemJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
, provided in LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, OS/2OS/2OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
, and AIXAIX operating systemAIX AIX AIX (Advanced Interactive eXecutive, pronounced "a i ex" is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms...
. Supports extents. - JXFS used in AmigaOSAmigaOSAmigaOS is the default native operating system of the Amiga personal computer. It was developed first by Commodore International, and initially introduced in 1985 with the Amiga 1000...
4.1. - LisaFS - Filesystem used by Apple LisaApple LisaThe Apple Lisa—also known as the Lisa—is a :personal computer designed by Apple Computer, Inc. during the early 1980s....
's operating system. Unique in that it allowed two different files with exactly same name ("foo" and "foo"). - LFS – 4.4BSD implementation of a log-structured file systemLog-structured file systemA log-structured filesystem is a file system design first proposed in 1988 by John K. Ousterhout and Fred Douglis. Designed for high write throughput, all updates to data and metadata are written sequentially to a continuous stream, called a log...
- MFSMacintosh File SystemMacintosh File System is a volume format created by Apple Computer for storing files on 400K floppy disks. MFS was introduced with the Macintosh 128K in January 1984....
– Macintosh File System, used on early Mac OSMac OSMac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...
systems. Succeeded by Hierarchical File System (HFS). - Next3Next3Next3 is a journaled file system for Linux based on ext3 which adds snapshots support, yet retains compatibility to the ext3 on-disk format. Next3 is implemented as open-source software, licensed under the GPL license.-Background:...
– A form of ext3Ext3The ext3 or third extended filesystem is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian...
with snapshots support. - MFSTivo's Media File SystemThe MFS or Media File System is a proprietary file system used on Tivo hard drives for fault tolerant real-time recording of live TV.Although MFS is still not particularly well understood by programmers unaffiliated with the Tivo corporation, enough is known about the file system to be able to do...
– TiVo's Media File System, a proprietary fault tolerant format used on TivoTiVoTiVo is a digital video recorder developed and marketed by TiVo, Inc. and introduced in 1999. TiVo provides an on-screen guide of scheduled broadcast programming television programs, whose features include "Season Pass" schedules which record every new episode of a series, and "WishList"...
hard drives for real time recording from live TV. - Minix file systemMINIX file system-History:MINIX was written from scratch by Andrew S. Tanenbaum in the 1980s, as a Unix-like operating system whose source code could be used freely in education...
– Used on MinixMinixMINIX is a Unix-like computer operating system based on a microkernel architecture created by Andrew S. Tanenbaum for educational purposes; MINIX also inspired the creation of the Linux kernel....
systems - NILFSNILFSNILFS is a log-structured file system implementation for Linux. It is being developed by Nippon Telegraph and Telephone Corporation CyberSpace Laboratories and released under the terms of the GNU General Public License .Version 2 of the filesystem, known as NILFS2, is included in Linux kernel...
– Linux implementation of a log-structured file systemLog-structured file systemA log-structured filesystem is a file system design first proposed in 1988 by John K. Ousterhout and Fred Douglis. Designed for high write throughput, all updates to data and metadata are written sequentially to a continuous stream, called a log... - NTFSNTFSNTFS is the standard file system of Windows NT, including its later versions Windows 2000, Windows XP, Windows Server 2003, Windows Server 2008, Windows Vista, and Windows 7....
– (NT File System) Used on MicrosoftMicrosoftMicrosoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
's Windows NTWindows NTWindows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
-based operating systems - NetWare File SystemNetWare File SystemIn computing, a NetWare File System 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 the default and only file system for the SYS volume...
- The original NetWareNovell NetWareNetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, with network protocols based on the archetypal Xerox Network Systems stack....
2.x - 5.x file system, used optionally by later versions. - NSSNovell Storage ServicesNovell Storage Services is a file system used by the Novell NetWare operating system. Recently support of NSS was introduced to SUSE Linux via low-level network NCPFS protocol...
– Novell Storage Services. This is a new 64-bit journaling file systemJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
using a balanced tree algorithm. Used in NetWareNovell NetWareNetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, with network protocols based on the archetypal Xerox Network Systems stack....
versions 5.0-up and recently ported to LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
. - OneFS - One File System. This is a fully journaled, distributed file system used by IsilonIsilon SystemsIsilon Systems, a division of EMC, is headquartered in Seattle, Washington, USA and sells clustered storage systems and software for digital content and other unstructured data, which includes but is not limited to video, audio, digital images, computer models, PDF files, scanned information, and...
. OneFS uses FlexProtect and Reed-Solomon encodings to support up to four simultaneous disk failures. - OFSAmiga Old File SystemOn the Amiga, the Old File System was the filesystem for Amiga OS before the Amiga Fast File System. Even though it used 512-byte blocks, it reserved the first small portion of each block for metadata, leaving an actual data block capacity of 488 bytes per block...
– Old File System, on Amiga. Good for floppies, but fairly useless on hard drives. - PFSProfessional File SystemThe Professional File System is a filesystem originally developed commercially for the Amiga, it is now distributed on Aminet with a 4-clause BSD license. PFS tends to perform very well, due to the simplicity of design. Compatible successor of Ami-FileSafe....
– and PFS2, PFS3, etc. Technically interesting file system available for the AmigaAmigaThe Amiga is a family of personal computers that was sold by Commodore in the 1980s and 1990s. The first model was launched in 1985 as a high-end home computer and became popular for its graphical, audio and multi-tasking abilities...
, performs very well under a lot of circumstances. Very simple and elegant. - ProDOSProDOSProDOS was the name of two similar operating systems for the Apple II series of personal computers. The original ProDOS, renamed ProDOS 8 in version 1.2, was the last official operating system usable by all Apple II series computers, and was distributed from 1983 to 1993...
- 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 IIgsApple IIGSThe Apple , the fifth and most powerful model in the Apple II series of personal computers produced by Apple Computer. The "GS" in the name stands for Graphics and Sound, referring to its enhanced graphics and sound capabilities, both of which greatly surpassed previous models of the line... - Qnx4fsQnx4fsQNX4FS is an extent-based file system used by the QNX4 and QNX6 operating systems.As the file system uses soft updates, it remains consistent even after a power failure, without using journaling. Instead, the writes are carefully ordered and flushed to disk at appropriate intervals so that the...
- File system that is used in QNXQNXQNX is a commercial Unix-like real-time operating system, aimed primarily at the embedded systems market. The product was originally developed by Canadian company, QNX Software Systems, which was later acquired by Canadian BlackBerry-producer Research In Motion.-Description:As a microkernel-based...
version 4 and 6. - Qnx6fs - New copy-on-writeCopy-on-writeCopy-on-write is an optimization strategy used in computer programming. The fundamental idea is that if multiple callers ask for resources which are initially indistinguishable, they can all be given pointers to the same resource...
file system presented in QNXQNXQNX is a commercial Unix-like real-time operating system, aimed primarily at the embedded systems market. The product was originally developed by Canadian company, QNX Software Systems, which was later acquired by Canadian BlackBerry-producer Research In Motion.-Description:As a microkernel-based...
6.4.0 and used as default since 6.4.1. - ReiserFSReiserFSReiserFS is a general-purpose, journaled computer file system designed and implemented by a team at Namesys led by Hans Reiser. ReiserFS is currently supported on Linux . Introduced in version 2.4.1 of the Linux kernel, it was the first journaling file system to be included in the standard kernel...
– File system that uses journalingJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system... - Reiser4Reiser4Reiser4 is a computer file system, successor to the ReiserFS file system, developed from scratch by Namesys and sponsored by DARPA as well as Linspire...
– File system that uses journalingJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
, newest version of ReiserFS - Reliance – Datalight's transactional file system for high reliability applications
- Reliance Nitro – Tree-based transactional file system developed for high-performance embedded systems, from Datalight
- S51K – AT&T UNIX System V 1KB Filesystem, used by SCO OpenServerSCO OpenServerSCO OpenServer, previously SCO UNIX and SCO Open Desktop , is, misleadingly, a closed source version of the Unix computer operating system developed by Santa Cruz Operation and now maintained by the SCO Group....
- SkyFS - Developed for SkyOSSkyOSSkyOS was a prototype commercial, proprietary, graphical desktop operating system written for the x86 computer architecture. As of January 30, 2009 development has halted and no plans to resume its development have been announced.- History :...
to replace BFS as the operating system's main file system. It is based on BFS, but contains many new features. - SFSSmart File SystemThe Smart File System is a journaling filesystem used on Amiga computers. It is designed for performance, scalability and integrity...
– Smart File System, journaling file systemJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
available for the Amiga platforms. - SpadFSSpadFSSpadFS is an experimental file system for Linux developed by Mikuláš Patočka. SpadFS was first presented at the end of 2006. "Spad" is an abbreviation for Czech Systém pro Psychopaty A Debily ....
- Linux - non-journaling, hashing lookup - STL (standard language file system) - a file system developed by IBM.
- TRFS - Experimental, design only
- Tux3Tux3Tux3 is an open-source versioning filesystem created by Daniel Phillips. He introduced the filesystem as a public replacement for his Tux2 filesystem which had encountered licensing issues due to the filing of several patents. Phillips had previously created the Htree directory indexing system...
- An experimental versioning file system intended as a replacement for ext3 - UDFUniversal Disk FormatUniversal Disk Format is an implementation of the specification known as ISO/IEC 13346 and ECMA-167 and is an open vendor-neutral file system for computer data storage for a broad range of media. In practice, it has been most widely used for DVDs and newer optical disc formats, supplanting ISO 9660...
– Packet based file system for WORM/RW media such as CD-RW and DVD. - UFSUnix File SystemThe Unix file system is a file system used by many Unix and Unix-like operating systems. It is also called the Berkeley Fast File System, the BSD Fast File System or FFS...
– Unix File System, used on Solaris and older BSD systems - UFS2 – Unix File System, used on newer BSD systems
- VxFSVERITAS File SystemThe 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...
VeritasVERITAS SoftwareVeritas Software Corp. was an international software company that was founded in 1983 as Tolerant Systems, renamed Veritas Software Corp. in 1989, and merged with Symantec in 2005. It was headquartered in Mountain View, California...
file system, first commercial journaling file systemJournaling file systemA journaling file system is a file system that keeps track of the changes that will be made in a journal before committing them to the main file system...
; HP-UXHP-UXHP-UX is Hewlett-Packard's proprietary implementation of the Unix operating system, based on UNIX System V and first released in 1984...
, Solaris, LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, AIXAIX operating systemAIX AIX AIX (Advanced Interactive eXecutive, pronounced "a i ex" is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms... - VLIR (Variable Length Indexed Record) – a filesystem extension added by Berkeley Softworks to CBMFS, allowing full random access read and write operations, for computers running GEOSGEOS (8-bit operating system)GEOS is an operating system from Berkeley Softworks . Originally designed for the Commodore 64 and released in 1986, it provided a graphical user interface for this popular 8-bit computer.GEOS closely resembled early versions of Mac OS and included a graphical word processor and paint program...
. - WAFLWrite Anywhere File LayoutThe Write Anywhere File Layout is a file layout that supports large, high-performance RAID arrays, quick restarts without lengthy consistency checks in the event of a crash or power failure , and growing the filesystems size quickly. It was designed by NetApp for use in its storage appliances...
– Write Anywhere File Layout. High performance, log-structuredLog-structured file systemA log-structured filesystem is a file system design first proposed in 1988 by John K. Ousterhout and Fred Douglis. Designed for high write throughput, all updates to data and metadata are written sequentially to a continuous stream, called a log...
like file system. WAFL uses RAID-DP to protect against multiple disk failures, and NVRAM for transaction log replays. Used on NetApp systems - XFSXFSXFS is a high-performance journaling file system created by Silicon Graphics, Inc. It is the default file system in IRIX releases 5.3 and onwards and later ported to the Linux kernel. XFS is particularly proficient at parallel IO due to its allocation group based design...
– Used on SGISilicon GraphicsSilicon Graphics, Inc. was a manufacturer of high-performance computing solutions, including computer hardware and software, founded in 1981 by Jim Clark...
IRIXIRIXIRIX is a computer operating system developed by Silicon Graphics, Inc. to run natively on their 32- and 64-bit MIPS architecture workstations and servers. It was based on UNIX System V with BSD extensions. IRIX was the first operating system to include the XFS file system.The last major version...
and LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
systems - ZFSZFSIn computing, ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include data integrity verification against data corruption modes , support for high storage capacities, integration of the concepts of filesystem and volume management,...
- Sun MicrosystemsSun MicrosystemsSun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
ZFSZFSIn computing, ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include data integrity verification against data corruption modes , support for high storage capacities, integration of the concepts of filesystem and volume management,...
open source specification ported to IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
zSeriesZSeriesIBM System z, or earlier IBM eServer zSeries, is a brand name designated by IBM to all its mainframe computers.In 2000, IBM rebranded the existing System/390 to IBM eServer zSeries with the e depicted in IBM's red trademarked symbol, but because no specific machine names were changed for...
systems.
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.- BtrfsBtrfsBtrfs is a GPL-licensed copy-on-write file system for Linux.Development began at Oracle Corporation in 2007....
- A filesystem based on B-TreeB-treeIn computer science, a B-tree is a tree data structure that keeps data sorted and allows searches, sequential access, insertions, and deletions in logarithmic time. The B-tree is a generalization of a binary search tree in that a node can have more than two children...
s, created by Oracle CorporationOracle CorporationOracle Corporation is an American multinational computer technology corporation that specializes in developing and marketing hardware systems and enterprise software products – particularly database management systems...
. - HAMMER - DragonflyBSD's primary filesystem, created by Matt DillonMatt Dillon (computer scientist)Matthew Dillon is a computer scientist living in Berkeley, California. He is best known for his contributions to FreeBSD and for starting the DragonFly BSD project....
- Reliance – A transactional file system with CRCsCyclic redundancy checkA cyclic redundancy check is an error-detecting code commonly used in digital networks and storage devices to detect accidental changes to raw data...
, created by Datalight. - Reliance Nitro – A tree-based transactional file system with CRCs, developed for high performance and reliability in embedded systems, from Datalight.
- ZFSZFSIn computing, ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include data integrity verification against data corruption modes , support for high storage capacities, integration of the concepts of filesystem and volume management,...
– Created by Sun MicrosystemsSun MicrosystemsSun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
for use on Solaris 10 and OpenSolarisOpenSolarisOpenSolaris was an open source computer operating system based on Solaris created by Sun Microsystems. It was also the name of the project initiated by Sun to build a developer and user community around the software...
, ported to FreeBSDFreeBSDFreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
7.0, NetBSDNetBSDNetBSD is a freely available open source version of the Berkeley Software Distribution Unix operating system. It was the second open source BSD descendant to be formally released, after 386BSD, and continues to be actively developed. The NetBSD project is primarily focused on high quality design,...
(as of 08/2009) and to FUSEFilesystem in UserspaceFilesystem in Userspace is a loadable kernel module for Unix-like computer operating systems that lets non-privileged users create their own file systems without editing kernel code...
(not to be confused with the two zFSes from IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
)
File systems optimized for flash memory, solid state media
Solid state media, like flash memoryFlash memory
Flash memory is a non-volatile computer storage chip that can be electrically erased and reprogrammed. It was developed from EEPROM and must be erased in fairly large blocks before these can be rewritten with new data...
, are similar to disks in their interfaces, but have different problems. While practically eliminating seek times, they require special handling such as wear leveling
Wear leveling
Wear leveling is a technique for prolonging the service life of some kinds of erasable computer storage media, such as Flash memory used in solid-state drives and USB Flash drives...
and different error detection and correction
Error detection and correction
In information theory and coding theory with applications in computer science and telecommunication, error detection and correction or error control are techniques that enable reliable delivery of digital data over unreliable communication channels...
algorithms.
- ETFS - Embedded Transactional File System. Designed primarily for NAND devices by QNX Software SystemsQNXQNX is a commercial Unix-like real-time operating system, aimed primarily at the embedded systems market. The product was originally developed by Canadian company, QNX Software Systems, which was later acquired by Canadian BlackBerry-producer Research In Motion.-Description:As a microkernel-based...
. - exFATExFATexFAT is a proprietary, patent-pending file system designed especially for USB flash drives. Developed by Microsoft, it is supported in Windows XP and Windows Server 2003 with update KB955704, Windows Embedded CE 6.0, Windows Vista with Service Pack 1, Windows Server 2008, Windows 7, Windows...
- MicrosoftMicrosoftMicrosoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
proprietary system intended for flash drives but often incorrectly called FAT64 - ExtremeFFS - Internal file system for SSDs.
- FFS2 (presumably preceded by FFS1), one of the earliest flash file systems. Developed and patented by MicrosoftMicrosoftMicrosoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
in the early 1990s. - JFFSJFFSThe Journaling Flash File System is a log-structured file system for use on NOR flash memory devices on the Linux operating system. It has been superseded by JFFS2.- Design :...
– Original log structured Linux file system for NOR flash media - JFFS2JFFS2Journalling Flash File System version 2 or JFFS2 is a log-structured file system for use with flash memory devices. It is the successor to JFFS. JFFS2 has been included in the Linux kernel since the 2.4.10 release. JFFS2 is also available for a couple of bootloaders like Das U-Boot, Open...
– Successor of JFFS, for NAND and NOR flash - LogFSLogFSLogFS 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....
– Intended to replace JFFS2, better scalability. In early development. - Non-Volatile File System -- the "non-volatile file system" for flash memoryFlash memoryFlash memory is a non-volatile computer storage chip that can be electrically erased and reprogrammed. It was developed from EEPROM and must be erased in fairly large blocks before these can be rewritten with new data...
introduced by Palm, Inc.Palm, Inc.Palm, Inc., was a smartphone manufacturer headquartered in Sunnyvale, California, that was responsible for products such as the Pre and Pixi as well as the Treo and Centro smartphones. Previous product lines include the PalmPilot, Palm III, Palm V, Palm VII, Zire and Tungsten. While their older...
. - OneFS - OneFS is a file system utilized by IsilonIsilon SystemsIsilon Systems, a division of EMC, is headquartered in Seattle, Washington, USA and sells clustered storage systems and software for digital content and other unstructured data, which includes but is not limited to video, audio, digital images, computer models, PDF files, scanned information, and...
. It supports selective placement of meta-data directly onto flash SSD. - Segger Microcontroller SystemsSegger Microcontroller SystemsSegger Microcontroller Systems is a multinational company dealing in middleware for embedded devices and development tools. The company, founded in 1991, is headquartered in Hilden, Germany with a US office in Westminster, Massachusetts....
emFile - File system for deeply embedded applications which supports both NAND and NOR flashes. Wear leveling, fast read and write, and very low RAM usage. - TFATTransaction-Safe FAT File SystemTransaction-Safe FAT File System refers 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 in cases of power loss or unexpected removal of the drive...
– A transactional version of the FAT filesystem. - TrueFFS - Internal file system for SSDs, implementing error correction, bad block re-mapping and wear levelling.
- UBIFSUBIFSThe Unsorted Block Image File System is a successor to JFFS2, and competitor to LogFS, as a file system for use with raw flash memory media. Development began in earnest in 2007, with the first stable release made to Linux kernel 2.6.27 in October 2008.Note that UBIFS works on top of an Unsorted...
– Successor of JFFS2 optimized to utilize non-volatile DRAM - UFFS - Ultra low cost flash file system for embedded system
- Unison RTOS - Fsys-Nand/Nor small footprint low cost flash file system for embedded systems
- Write Anywhere File LayoutWrite Anywhere File LayoutThe Write Anywhere File Layout is a file layout that supports large, high-performance RAID arrays, quick restarts without lengthy consistency checks in the event of a crash or power failure , and growing the filesystems size quickly. It was designed by NetApp for use in its storage appliances...
- WAFL is an internal file system utilized by NetApp within their DataONTAP OS, originally optimized to use non-volatile DRAM - XCFiles – an exFAT implementation from Datalight for Wind RiverWind River SystemsWind River Systems, Inc. is a company providing embedded systems, development tools for embedded systems, middleware, and other types of software. The company was founded in Berkeley, California in 1981 by Jerry Fiddler and David Wilner. On June 4, 2009, Wind River announced that Intel had bought...
VxWorksVxWorksVxWorks is a real-time operating system developed as proprietary software by Wind River Systems of Alameda, California, USA. First released in 1987, VxWorks is designed for use in embedded systems.- History :...
and other embedded operating systems - YAFFSYAFFSYAFFS was designed and written by Charles Manning, of Whitecliffs, New Zealand, for the company .Yaffs1 is the first version of this file system and works on NAND chips that have 512 byte pages + 16 byte spare areas. These older chips also generally allow 2 or 3 write cycles per page, which...
– A Log structured file system designed for NAND flash, but also used with NOR flash. - ZFSZFSIn computing, ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include data integrity verification against data corruption modes , support for high storage capacities, integration of the concepts of filesystem and volume management,...
- Allows placing write-ahead log (ZIL) on flash, and using flash as a second-level read cache (L2ARC)
Record-oriented file systems
In record-oriented file systemsRecord-oriented filesystem
In computer science, a record-oriented filesystem is a file system where files are stored as collections of records. There are several different record formats; the details vary depending on the particular system...
files are stored as a collection of records
Record (computer science)
In computer science, a record is an instance of a product of primitive data types called a tuple. In C it is the compound data in a struct. Records are among the simplest data structures. A record is a value that contains other values, typically in fixed number and sequence and typically indexed...
. They are typically associated with mainframe
Mainframe computer
Mainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.The term originally referred to the...
and minicomputer
Minicomputer
A minicomputer is a class of multi-user computers that lies in the middle range of the computing spectrum, in between the largest multi-user systems and the smallest single-user systems...
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
Database
A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality , in a way that supports processes requiring this information...
s than with other file systems.
- Files-11Files-11Files-11, also known as on-disk structure, is the file system used by Hewlett-Packard's OpenVMS operating system, and also by the older RSX-11...
– early versions were record-oriented; support for "streams" was added later - Michigan Terminal SystemMichigan Terminal SystemThe Michigan Terminal System is one of the first time-sharing computer operating systems. Initially developed in 1967 at the University of Michigan for use on IBM S/360-67, S/370 and compatible mainframe computers, it was developed and used by a consortium of eight universities in the United...
(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. - OS4000OS4000OS4000 is a proprietary operating system introduced by GEC Computers Limited in 1977 as the successor to GEC DOS, for its range of GEC 4000 series 16-bit, and later 32-bit, minicomputers...
for GEC's OS4000 operating system, on the GEC 4000 seriesGEC 4000 seriesThe GEC 4000 was a series of 16/32-bit minicomputers produced by GEC Computers Ltd. of the UK during the 1970s, 1980s and early 1990s.- History :...
minicomputers - Queued sequential access methodQueued Sequential Access MethodIn IBM mainframe operating systems, Queued sequential access method is an access method to read and write datasets sequentially. QSAM is available on OS/360, OS/VS2, MVS, z/OS, and related high-end operating systems....
(QSAM) – also for IBM's z/OSZ/OSz/OS is a 64-bit operating system for mainframe computers, produced by IBM. It derives from and is the successor to OS/390, which in turn followed a string of MVS versions.Starting with earliest:*OS/VS2 Release 2 through Release 3.8...
and z/VSE operating systems; see Access methods and Data set (IBM mainframe)Data set (IBM mainframe)data set , dataset , is a computer file having a record organization. The term pertains to the IBM mainframe operating system line, starting with OS/360, and is still used by its successors, including the current z/OS. Those systems historically preferred this term over a file...
for more examples - Pick Operating SystemPick operating systemThe Pick operating system is a demand-paged, multiuser, virtual memory, time-sharing operating system based around a unique "multivalued" database. Pick is used primarily for business data processing...
- A record-oriented filesystem and database that uses hash-coding to store data. - RSD (record sequential delimited) - A record-oriented file system from IBM
- Structured File Server (SFS) — A record-oriented file system from IBM, originally part of the Encina system, now integrated into CICSCICSCustomer Information Control System is a transaction server that runs primarily on IBM mainframe systems under z/OS and z/VSE.CICS is a transaction manager designed for rapid, high-volume online processing. This processing is mostly interactive , but background transactions are possible...
Transaction Server. - Virtual storage access methodVirtual storage access methodVirtual storage access method an IBM disk file storage access method, first used in the OS/VS1, OS/VS2 Release 1 and Release 2 operating systems, later used throughout the Multiple Virtual Storage architecture and now in z/OS...
(VSAM) – for IBM's z/OSZ/OSz/OS is a 64-bit operating system for mainframe computers, produced by IBM. It derives from and is the successor to OS/390, which in turn followed a string of MVS versions.Starting with earliest:*OS/VS2 Release 2 through Release 3.8...
and z/VSE operating systems
Shared disk file systems
Shared disk file systems (also called shared storage file systems, SAN file system, Clustered file systemClustered file system
A clustered file system is a file system which is shared by being simultaneously mounted on multiple servers. There are several approaches to clustering, most of which do not employ a clustered file system...
or even cluster file systems) are primarily used in a storage area network
Storage area network
A storage area network is a dedicated network that provides access to consolidated, block level data storage. SANs are primarily used to make storage devices, such as disk arrays, tape libraries, and optical jukeboxes, accessible to servers so that the devices appear like locally attached devices...
where all nodes directly access the block storage 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
High-availability cluster
High-availability clusters are groups of computers that support server applications that can be reliably utilized with a minimum of down-time. They operate by harnessing redundant computers in groups or clusters that provide continued service when system components fail...
together with storage on hardware RAID
RAID
RAID is a storage technology that combines multiple disk drive components into a logical unit...
. Shared disk file systems normally do not scale over 64 or 128 nodes.
Shared disk file systems may be symmetric where metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
is distributed among the nodes or asymmetric
Asymmetry
Asymmetry is the absence of, or a violation of, symmetry.-In organisms:Due to how cells divide in organisms, asymmetry in organisms is fairly usual in at least one dimension, with biological symmetry also being common in at least one dimension....
with centralized metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
servers.
Parallel filesystem - file systems with support for parallel applications, all nodes may be accessing the same files at the same time, concurrently reading and writing. Data for a single file is striped across multiple storage nodes to provide scalable performance to individual files. Examples of this include: Panasas ActiveScale, Lustre, GPFS and Sistina. NFSv4.1 will feature an extension to the NFS standard that supports parallel IO.
- CXFSCXFSThe CXFS file system is a proprietary shared disk file system designed by Silicon Graphics specifically to be used in a Storage area network environment....
(Clustered XFS) from Silicon GraphicsSilicon GraphicsSilicon Graphics, Inc. was a manufacturer of high-performance computing solutions, including computer hardware and software, founded in 1981 by Jim Clark...
(SGI). Available for AIX, IRIX, Linux, Solaris and Windows. Asymmetric. - DataPlow SAN File System (SFS) from DataPlow. Available for IRIX, Linux, Solaris and Windows. Asymmetric.
- EMC Celerra HighRoadEMC Celerra HighRoadEMC Celerra HighRoad or lately re-named MPFS is a Distributed Filesystem. A client-resident agent interacts with the Celerra File Server via a special protocol FMP ....
from EMCEMC CorporationEMC Corporation , a Financial Times Global 500, Fortune 500 and S&P 500 company, develops, delivers and supports information infrastructure and virtual infrastructure hardware, software, and services. EMC is headquartered in Hopkinton, Massachusetts, USA.Former Intel executive Richard Egan and his...
. Available for Linux, AIX, HP-UX, IRIX, Solaris and Windows. Asymmetric. - Files-11Files-11Files-11, also known as on-disk structure, is the file system used by Hewlett-Packard's OpenVMS operating system, and also by the older RSX-11...
on VMSclusterVMSclusterA VMScluster is a computer cluster involving a group of computers running the OpenVMS operating system. Whereas tightly coupled multiprocessor systems run a single copy of the operating system, a VMScluster is loosely coupled: each machine runs its own copy of OpenVMS, but the disk storage, lock...
s, released by DECDigital Equipment CorporationDigital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
in 1983, now from HPHewlett-PackardHewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
. Symmetric. - Global File SystemGlobal File SystemIn computing, the Global File System is a shared disk file system for Linux computer clusters. This is not to be confused with the Google File System, a proprietary distributed filesystem developed by Google....
(GFS) from Red HatRed HatRed Hat, Inc. is an S&P 500 company in the free and open source software sector, and a major Linux distribution vendor. Founded in 1993, Red Hat has its corporate headquarters in Raleigh, North Carolina with satellite offices worldwide....
. Available for Linux under GPLGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. Symmetric (GDLM) or Asymmetric (GULM). - IBM General Parallel File System (GPFS) Windows, Linux, AIX . Parallel
- HP Cluster File System (CFS) (TruCluster) from HPHewlett-PackardHewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
. Available for Tru64 UNIXTru64 UNIXTru64 UNIX is a 64-bit UNIX operating system for the Alpha instruction set architecture , currently owned by Hewlett-Packard . Previously, Tru64 UNIX was a product of Compaq, and before that, Digital Equipment Corporation , where it was known as Digital UNIX .As its original name suggests, Tru64...
. - NasanNasanNasan is a shared disk file system created by DataPlow, that features the ability to give shared, block-level access to a disk volume from multiple client computers without causing file system corruption. DataPlow sells their software directly on a per-seat basis. Each client must purchase the...
File System from DataPlow. Available for Linux and Solaris. Asymmetric. - Oracle ACFSOracle ACFSOracle Automatic Storage Management Cluster File System is a file system based on Oracle Automatic Storage Management . An Oracle ACFS file system is a layer on Oracle ASM and is configured with Oracle ASM storage. Oracle ASM, introduced in Oracle 10g, was originally intended to manage the data...
from Oracle CorporationOracle CorporationOracle Corporation is an American multinational computer technology corporation that specializes in developing and marketing hardware systems and enterprise software products – particularly database management systems...
. Available for Linux (Red Hat Enterprise Linux 5 and Oracle Enterprise LinuxOracle Enterprise LinuxOracle Linux, formerly known as Oracle Enterprise Linux, is a Red Hat Enterprise Linux-compatible distribution, repackaged and sold by Oracle, available under the GNU General Public License since late 2006....
5 only). Symmetric. - Oracle Cluster File SystemOCFSOCFS is a shared disk file system developed by Oracle Corporation and released under the GNU General Public License....
(OCFS and now OCFS2) from Oracle CorporationOracle CorporationOracle Corporation is an American multinational computer technology corporation that specializes in developing and marketing hardware systems and enterprise software products – particularly database management systems...
. Available for Linux under GPLGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. Symmetric. - PolyServe file system (PSFS) from PolyServe http://www.polyserve.com/ is used in their PolyServe Matrix Server which focus on exporting to clients over CIFS or NFS as well as Microsoft SQL Server and Oracle 9i RAC and 10g. Available for Linux and Windows. Symmetric.
- StorNext File SystemStorNext File SystemStorNext File System is a shared disk file system made by Quantum Corporation. It is installed on hosts that are connected to the same disk array in a storage area network . Client systems are not required to run the same operating system to access a shared filesystem containing StorNext data...
from Quantum. Asymmetric. Available for AIXAIX operating systemAIX AIX AIX (Advanced Interactive eXecutive, pronounced "a i ex" is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms...
, HP-UXHP-UXHP-UX is Hewlett-Packard's proprietary implementation of the Unix operating system, based on UNIX System V and first released in 1984...
, IRIXIRIXIRIX is a computer operating system developed by Silicon Graphics, Inc. to run natively on their 32- and 64-bit MIPS architecture workstations and servers. It was based on UNIX System V with BSD extensions. IRIX was the first operating system to include the XFS file system.The last major version...
, LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, Mac OSMac OSMac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...
, Solaris and WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
. Interoperable with XsanXsanXsan is Apple Inc.'s storage area network or clustered file system for Mac OS X. 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 computers can read and write to the same storage volume at...
. Formerly known as CVFS. - Blue Whale Clustered file systemBlue Whale Clustered file systemBlue Whale Clustered file system is a shared disk file system made by Tianjin Zhongke Blue Whale Information Technologies Company in China.-Overview:...
(BWFS) from Zhongke Blue Whale. Asymmetric. Available for Microsoft WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, and Mac OS XMac OS XMac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
. - QFSQFSQFS is an open source filesystem from Sun Microsystems. It is tightly integrated with SAM, the Storage and Archive Manager, and hence is often referred to as SAM-QFS. SAM provides the functionality of a Hierarchical Storage Manager....
from Sun MicrosystemsSun MicrosystemsSun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
. Available for Linux (client only) and Solaris (metadata server and client). Asymmetric. - Veritas Storage FoundationVeritas Storage FoundationVeritas Storage Foundation, previously known as Veritas Foundation Suite, combines Veritas Volume Manager and Veritas File System to provide a complete solution for online storage management...
from SymantecSymantecSymantec Corporation is the largest maker of security software for computers. The company is headquartered in Mountain View, California, and is a Fortune 500 company and a member of the S&P 500 stock market index.-History:...
. Available for AIX, HP-UX, Linux and Solaris. Asymmetric. - XsanXsanXsan is Apple Inc.'s storage area network or clustered file system for Mac OS X. 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 computers can read and write to the same storage volume at...
from Apple Inc.. Available for Mac OS. Asymmetric. Interoperable with StorNext File SystemStorNext File SystemStorNext File System is a shared disk file system made by Quantum Corporation. It is installed on hosts that are connected to the same disk array in a storage area network . Client systems are not required to run the same operating system to access a shared filesystem containing StorNext data...
. - VMFSVMware VMFSVMware VMFS is VMware, Inc.'s cluster file system. It is used by VMware ESX Server and the company's flagship server virtualization suite, VMware Infrastructure. It was developed and is used to store virtual machine disk images, including snapshots...
from VMwareVMwareVMware, Inc. is a company providing virtualization software founded in 1998 and based in Palo Alto, California, USA. The company was acquired by EMC Corporation in 2004, and operates as a separate software subsidiary ....
/EMC CorporationEMC CorporationEMC Corporation , a Financial Times Global 500, Fortune 500 and S&P 500 company, develops, delivers and supports information infrastructure and virtual infrastructure hardware, software, and services. EMC is headquartered in Hopkinton, Massachusetts, USA.Former Intel executive Richard Egan and his...
. Available for VMware ESX ServerVMware ESX ServerVMware ESX is an enterprise-level computer virtualization product offered by VMware, Inc. ESX is a component of VMware's larger offering, VMware Infrastructure, and adds management and reliability services to the core server product...
. Symmetric.
Distributed file systems
Distributed file systemDistributed file system
Network file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...
s 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.
- 9P9P9P is a network protocol developed for the Plan 9 from Bell Labs distributed operating system as the means of connecting the components of a Plan 9 system. Files are key objects in Plan 9. They represent windows, network connections, processes, and almost anything else available in the operating...
, the Plan 9 from Bell LabsPlan 9 from Bell LabsPlan 9 from Bell Labs is a distributed operating system. It was developed primarily for research purposes as the successor to Unix by the Computing Sciences Research Center at Bell Labs between the mid-1980s and 2002...
and InfernoInferno (operating system)Inferno is a distributed operating system started at Bell Labs, but is now developed and maintained by Vita Nuova Holdings as free software. Inferno was based on the experience gained with Plan 9 from Bell Labs, and the further research of Bell Labs into operating systems, languages, on-the-fly...
distributed file system protocol. One implementation is v9fs. No ACLs. - Amazon S3Amazon S3Amazon S3 is an online storage web service offered by Amazon Web Services. Amazon S3 provides storage through web services interfaces...
- Andrew File SystemAndrew file systemThe Andrew File System is a distributed networked file system which uses a set of trusted servers to present a homogeneous, location-transparent file name space to all the client workstations. It was developed by Carnegie Mellon University as part of the Andrew Project. It is named after Andrew...
(AFS) is scalable and location independent, has a heavy client cacheCacheIn computer engineering, a cache is a component that transparently stores data so that future requests for that data can be served faster. The data that is stored within a cache might be values that have been computed earlier or duplicates of original values that are stored elsewhere...
and uses Kerberos for authentication. Implementations include the original from IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
(earlier TransarcTransarcTransarc Corporation was a private Pittsburgh-based software company founded in 1989 by Jeffrey Eppinger, Michael Kazar, Alfred Spector, and Dean Thompson of Carnegie Mellon University...
), ArlaArla (file system)Arla is an implementation of the AFS distributed file system developed at the Royal Institute of Technology in Stockholm.Arla was started by Björn Grönvall in 1993. Assar Westerlund and Johan Danielsson joined the project shortly thereafter. The project died down before it was usable.In the fall of...
and OpenAFSOpenAFSOpenAFS is an open source implementation of the Andrew distributed file system . AFS was originally developed at Carnegie Mellon University, and developed as a commercial product by the Transarc Corporation, which was subsequently acquired by IBM. At LinuxWorld on 15 August 2000, IBM their plans...
. - Apple Filing ProtocolApple Filing ProtocolThe Apple Filing Protocol is a network protocol that offers file services for Mac OS X and original Mac OS. In Mac OS X, AFP is one of several file services supported including Server Message Block , Network File System , File Transfer Protocol , and WebDAV...
(AFP) from Apple Inc.. AFP may use Kerberos authentication. - DCE Distributed File SystemDCE Distributed File SystemThe DCE Distributed File System is the remote file access protocol used with the Distributed Computing Environment. It was based on the AFS Version 3.0 protocol that was developed commercially by Transarc Corporation...
(DCEDistributed Computing EnvironmentThe Distributed Computing Environment is a software system developed in the early 1990s by a consortium that included Apollo Computer , IBM, Digital Equipment Corporation, and others. The DCE supplies a framework and toolkit for developing client/server applications...
/DFS) from IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
(earlier TransarcTransarcTransarc Corporation was a private Pittsburgh-based software company founded in 1989 by Jeffrey Eppinger, Michael Kazar, Alfred Spector, and Dean Thompson of Carnegie Mellon University...
) is similar to AFS and focus on full POSIXPOSIXPOSIX , an acronym for "Portable Operating System Interface", is a family of standards specified by the IEEE for maintaining compatibility between operating systems...
file system semantics and high availabilityHigh availabilityHigh availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period....
. Available for AIXAIX operating systemAIX AIX AIX (Advanced Interactive eXecutive, pronounced "a i ex" is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms...
and Solaris under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - File Access ListenerFile Access ListenerFile Access Listener is an implementation of the Data Access Protocol , a network file system protocol developed by Digital Equipment Corporation as part of DECnet suite of network protocols....
(FAL) is an implementation of the Data Access Protocol (DAP) which is part of the DECnetDECnetDECnet 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 into a networking powerhouse in the 1980s...
suite of network protocols created by Digital Equipment CorporationDigital Equipment CorporationDigital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
. - Microsoft Office GrooveMicrosoft Office GrooveMicrosoft SharePoint Workspace, previously known as Microsoft Office Groove, is a desktop application designed for document collaboration in teams with members who are regularly off-line or who do not share the same network security clearance....
shared workspace, used for DoHyki - NetWare Core ProtocolNetWare Core ProtocolThe NetWare Core Protocol is a network protocol used in some products from Novell, Inc. It is usually associated with the NetWare operating system, but parts of it have been implemented on other platforms such as Linux, Windows NT and various flavors of Unix.It is used to access file, print,...
(NCP) from NovellNovellNovell, Inc. is a multinational software and services company. It is a wholly owned subsidiary of The Attachmate Group. It specializes in network operating systems, such as Novell NetWare; systems management solutions, such as Novell ZENworks; and collaboration solutions, such as Novell Groupwise...
is used in networks based on NetWareNovell NetWareNetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, with network protocols based on the archetypal Xerox Network Systems stack....
. - Network File System (NFS) originally from Sun MicrosystemsSun MicrosystemsSun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
is the standard in UNIX-based networks. NFS may use Kerberos authentication and a client cacheCacheIn computer engineering, a cache is a component that transparently stores data so that future requests for that data can be served faster. The data that is stored within a cache might be values that have been computed earlier or duplicates of original values that are stored elsewhere...
. (4.1 only) - OS4000OS4000OS4000 is a proprietary operating system introduced by GEC Computers Limited in 1977 as the successor to GEC DOS, for its range of GEC 4000 series 16-bit, and later 32-bit, minicomputers...
Linked-OS provides distributed filesystem across OS4000 systems. - Secure File System (SFS) http://elbe.borg.umn.edu/
- Self-certifying File SystemSelf-certifying File SystemIn computing, Self-certifying File System is a global and decentralized, distributed file system for Unix-like operating systems, while also providing transparent encryption of communications as well as authentication...
(SFS), a global network file system designed to securely allow access to file systems across separate administrative domains. - Server Message BlockServer Message BlockIn computer networking, Server Message Block , also known as Common Internet File System operates as an application-layer network protocol mainly used to provide shared access to files, printers, serial ports, and miscellaneous communications between nodes on a network. It also provides an...
(SMB) originally from IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
(but the most common version is modified heavily by MicrosoftMicrosoftMicrosoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
) 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 high availabilityHigh availability
High availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period....
and offline (disconnected) operation.
- CodaCoda (file system)Coda is a distributed file system developed as a research project at Carnegie Mellon University since 1987 under the direction of Mahadev Satyanarayanan. It descended directly from an older version of AFS and offers many similar features. The InterMezzo file system was inspired by Coda...
from Carnegie Mellon UniversityCarnegie Mellon UniversityCarnegie Mellon University is a private research university in Pittsburgh, Pennsylvania, United States....
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 LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under the GPLGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. - Distributed File System (Microsoft)Distributed File System (Microsoft)Distributed File System is a set of client and server services that allow an organization using Microsoft Windows servers to organize many distributed SMB file shares into a distributed file system...
(Dfs) from MicrosoftMicrosoftMicrosoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
focuses on location transparency and high availabilityHigh availabilityHigh availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period....
. Available for WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - InterMezzoInterMezzo (file system)InterMezzo is an obsolete distributed file system written for Linux, distributed under the GPL. The kernel component is not included in the current 2.6 kernel. It was included in the standard Linux kernel from kernel version 2.4.15 but was dropped from the 2.6 kernel...
from Cluster File SystemsCluster File SystemsCluster File Systems, Inc. is the company that originally developed the Lustre distributed file system. CFS was a privately held company with offices in the United States, and China.CFS was founded in 2001 by Dr. Peter Braam...
uses synchronization over HTTP. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under GPLGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
but no longer in development since the developers are working on LustreLustre (file system)Lustre is a massively parallel distributed file system, generally used for large scale cluster computing. The name Lustre is a portmanteau word derived from Linux and cluster...
. - Moose File SystemMoose File SystemMoose File System is a distributed file system developed by Gemius SA. The lead developer is Jakub Kruszona-Zawadzki. MooseFS aims to be fault-tolerant, scalable, POSIX compliant, general-purpose file system for datacenters...
(MooseFS) from Gemius SA 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 MAC OS X. Master server and chunkservers can also run on Solaris and Windows with Cygwin. - Tahoe-LAFS is an open source secure, decentralized, fault-tolerant filesystem utilizing encryption as the basis for a least-authority replicated design.
Distributed parallel file systems
Distributed parallelParallel computing
Parallel computing is a form of computation in which many calculations are carried out simultaneously, operating on the principle that large problems can often be divided into smaller ones, which are then solved concurrently . There are several different forms of parallel computing: bit-level,...
file systems stripe data over multiple servers for high performance. They are normally used in high-performance computing (HPC)
High-performance computing
High-performance computing uses supercomputers and computer clusters to solve advanced computation problems. Today, computer systems approaching the teraflops-region are counted as HPC-computers.-Overview:...
.
Some of the distributed parallel file systems use object storage device
Object storage device
An Object-based Storage Device is a computer storage device, similar to disk storage but working at a higher level. Instead of providing a block-oriented interface that reads and writes fixed sized blocks of data, an OSD organizes data into flexible-sized data containers, called objects...
(OSD) (In Lustre called OST) for chunks of data together with centralized metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
servers.
- Fraunhofer Parallel File SystemFhGFSThe Fraunhofer Parallel File System, also known as FraunhoferFS and abbreviated FhGFS, is a parallel file system, optimized for usage in the field of High Performance Computing. The most important aspect is data throughput. It is developed at the Fraunhofer Institute for Industrial Mathematics in...
(FhGFS) from the Fraunhofer SocietyFraunhofer SocietyThe Fraunhofer Society is a German research organization with 60 institutes spread throughout Germany, each focusing on different fields of applied science . It employs around 18,000, mainly scientists and engineers, with an annual research budget of about €1.65 billion...
Competence Center for High Performance Computing. Available free of charge for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under a proprietary license. (High availability features are on the roadmap.) - Parallel Virtual File System (PVFS, PVFS2). Developed to store virtual system images, with a focus on non shared writing optimizations. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under GPLGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. - Starfish is a POSIXPOSIXPOSIX , an acronym for "Portable Operating System Interface", is a family of standards specified by the IEEE for maintaining compatibility between operating systems...
-compatible, N-way redundant file system created by Digital Bazaar Inc. and published under a pseudo open source license. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
and Mac OSMac OSMac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...
. Windows support is available via Samba.
Distributed parallel fault-tolerant file systems
Distributed file systems, which also are parallelParallel computing
Parallel computing is a form of computation in which many calculations are carried out simultaneously, operating on the principle that large problems can often be divided into smaller ones, which are then solved concurrently . There are several different forms of parallel computing: bit-level,...
and fault tolerant, stripe and replicate data over multiple servers for high performance and to maintain data integrity
Data integrity
Data Integrity in its broadest meaning refers to the trustworthiness of system resources over their entire life cycle. In more analytic terms, it is "the representational faithfulness of information to the true state of the object that the information represents, where representational faithfulness...
. Even if a server fails no data is lost. The file systems are used in both high-performance computing (HPC)
High-performance computing
High-performance computing uses supercomputers and computer clusters to solve advanced computation problems. Today, computer systems approaching the teraflops-region are counted as HPC-computers.-Overview:...
and high-availability cluster
High-availability cluster
High-availability clusters are groups of computers that support server applications that can be reliably utilized with a minimum of down-time. They operate by harnessing redundant computers in groups or clusters that provide continued service when system components fail...
s.
All file systems listed here focus on high availability
High availability
High availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period....
, scalability
Scalability
In electronics scalability is the ability of a system, network, or process, to handle growing amount of work in a graceful manner or its ability to be enlarged to accommodate that growth...
and high performance unless otherwise stated below.
- CloudStoreCloudStoreCloudStore is Kosmix's C++ implementation of Google File System. It parallels the Hadoop project, which is implemented in Java. CloudStore supports incremental scalability, replication, checksumming for data integrity, client side fail-over and access from C++, Java and Python...
from KosmixKosmixKosmix was an American privately held company in Mountain View, California. Their website earned revenue from advertising related to its categorization engine. The engine organizes the Internet into topic pages allowing users to explore the Web by topic, "presenting a dashboard of relevant videos,...
is a Google File SystemGoogle File SystemGoogle File System is a proprietary distributed file system developed by Google Inc. for its own use. It is designed to provide efficient, reliable access to data using large clusters of commodity hardware...
workalike, available under Apache License 2.0Apache LicenseThe Apache License is a copyfree free software license authored by the Apache Software Foundation . The Apache License requires preservation of the copyright notice and disclaimer....
. - Cosmos (MicrosoftMicrosoftMicrosoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
internal) focuses on fault tolerance, high throughputThroughputIn communication networks, such as Ethernet or packet radio, throughput or network throughput is the average rate of successful message delivery over a communication channel. This data may be delivered over a physical or logical link, or pass through a certain network node...
and scalabilityScalabilityIn electronics scalability is the ability of a system, network, or process, to handle growing amount of work in a graceful manner or its ability to be enlarged to accommodate that growth...
. Designed for terabyteTerabyteThe terabyte is a multiple of the unit byte for digital information. The prefix tera means 1012 in the International System of Units , and therefore 1 terabyte is , or 1 trillion bytes, or 1000 gigabytes. 1 terabyte in binary prefixes is 0.9095 tebibytes, or 931.32 gibibytes...
and petabytePetabyteA petabyte is a unit of information equal to one quadrillion bytes, or 1000 terabytes. The unit symbol for the petabyte is PB...
sized data sets and processing with DryadDryad (programming)Dryad is an ongoing research project at Microsoft Research for a general purpose runtime for execution of data parallel applications. An application written for Dryad is modeled as a directed acyclic graph . The DAG defines the dataflow of the application, and the vertices of the graph defines the...
. - dCache by FermilabFermilabFermi National Accelerator Laboratory , located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics...
and DESYDESYThe DESY is the biggest German research center for particle physics, with sites in Hamburg and Zeuthen....
. A write once filesystem, accessible via various protocols (not mountable). Is available free of charge (although it is not Free/Open Source Software due to license restrictions on distribution of modified versions) - ExaFS distributed file system from ExanetExanetExanet Ltd., was a software company which provides scalable network-attached storage software solutions to OEM partners....
. Runs as part of ExaStore, a Linux based NAS solution that runs on commodity Intel based hardware, serving NFS v2/v3, SMB/CIFS and AFP to WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, Mac OSMac OSMac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...
, LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
and other UNIXUnixUnix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
clients. Available under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - FS-Manager from CDNetworksCDNetworksCDNetworks founded in 2000, is a full service content delivery network , with increasing business in the United States.-Content delivery services:...
focused on Content Delivery NetworkContent Delivery NetworkA content delivery network or content distribution network is a system of computers containing copies of data placed at various nodes of a network....
. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - Gfarm file systemGfarm file systemGfarm file system is an Open Source distributed file system, generally used for large scale cluster computing. The name is derived from the Grid Data Farm architecture it implements....
uses OpenLDAPOpenLDAPOpenLDAP Software is a free, open source implementation of the Lightweight Directory Access Protocol developed by the OpenLDAP Project. It is released under its own BSD-style license called the OpenLDAP Public License. LDAP is a platform-independent protocol. Several common Linux distributions...
or PostgreSQLPostgreSQLPostgreSQL, often simply Postgres, is an object-relational database management system available for many platforms including Linux, FreeBSD, Solaris, MS Windows and Mac OS X. It is released under the PostgreSQL License, which is an MIT-style license, and is thus free and open source software...
for metadata and FUSE or LUFS for mounting. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, FreeBSDFreeBSDFreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
, NetBSDNetBSDNetBSD is a freely available open source version of the Berkeley Software Distribution Unix operating system. It was the second open source BSD descendant to be formally released, after 386BSD, and continues to be actively developed. The NetBSD project is primarily focused on high quality design,...
and Solaris under X11 License. - General Parallel File SystemGeneral Parallel File SystemThe General Parallel File System is a high-performance shared-disk clustered file system developed by IBM. It is used by some of the supercomputers on the Top 500 List...
(GPFS) from IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
. Support replicationReplication (computer science)Replication is the process of sharing information so as to ensure consistency between redundant resources, such as software or hardware components, to improve reliability, fault-tolerance, or accessibility. It could be data replication if the same data is stored on multiple storage devices, or...
between attached block storage. Available for AIX, Linux and Windows. Symmetric or asymmetric (configurable). (proprietary) - GlusterFSGlusterFSGlusterFS is a scale-out NAS file system developed by Gluster. It aggregates various storage servers over Ethernet or Infiniband RDMA interconnect into one large parallel network file system. GlusterFS is based on a stackable user space design without compromising performance. It has found a...
is a general purpose distributed file system for scalable storage. It aggregates various storage bricks over Infiniband RDMA or TCP/IP interconnect into one large parallel network file system. Released under GNU General Public License v3. - Google File SystemGoogle File SystemGoogle File System is a proprietary distributed file system developed by Google Inc. for its own use. It is designed to provide efficient, reliable access to data using large clusters of commodity hardware...
(GFS) from GoogleGoogleGoogle Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...
focus on fault tolerance, high throughputThroughputIn communication networks, such as Ethernet or packet radio, throughput or network throughput is the average rate of successful message delivery over a communication channel. This data may be delivered over a physical or logical link, or pass through a certain network node...
and scalabilityScalabilityIn electronics scalability is the ability of a system, network, or process, to handle growing amount of work in a graceful manner or its ability to be enlarged to accommodate that growth...
. Only available for use through Google App EngineGoogle App EngineGoogle App Engine is a platform as a service cloud computing platform for developing and hosting web applications in Google-managed data centers. It virtualizes applications across multiple servers,...
. - IBRIX FusionIBRIX FusionIBRIX Fusion is a scalable parallel file system combined with integrated logical volume manager, availability features and a management interface. The software was produced, sold, and supported by IBRIX Incorporated of Billerica, Massachusetts. HP announced on July 17, 2009 that it had reached a...
from IBRIX. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - LustreLustre (file system)Lustre is a massively parallel distributed file system, generally used for large scale cluster computing. The name Lustre is a portmanteau word derived from Linux and cluster...
is a POSIXPOSIXPOSIX , an acronym for "Portable Operating System Interface", is a family of standards specified by the IEEE for maintaining compatibility between operating systems...
-compliant, high-performance filesystem originally developed by Cluster File SystemsCluster File SystemsCluster File Systems, Inc. is the company that originally developed the Lustre distributed file system. CFS was a privately held company with offices in the United States, and China.CFS was founded in 2001 by Dr. Peter Braam...
. Lustre has high availabilityHigh availabilityHigh availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period....
via storage failoverFailoverIn computing, failover is automatic switching to a redundant or standby computer server, system, or network upon the failure or abnormal termination of the previously active application, server, system, or network...
. Freely available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under GPLGNU General Public LicenseThe GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. - MogileFS from Danga InteractiveDanga InteractiveDanga Interactive is a software and Internet company most widely known for its LiveJournal service. The company's slogan is "We make cool stuff." The company was founded under the name Bradfitz, Inc., on August 27, 1999, by Brad Fitzpatrick, who also created LiveJournal...
is not POSIXPOSIXPOSIX , an acronym for "Portable Operating System Interface", is a family of standards specified by the IEEE for maintaining compatibility between operating systems...
compliant, uses a flat namespace, application level, uses MySQLMySQLMySQL officially, but also commonly "My Sequel") is a relational database management system that runs as a server providing multi-user access to a number of databases. It is named after developer Michael Widenius' daughter, My...
or Postgres for metadata and HTTP for transport. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
(but may be ported) under GPL. - OneFS distributed file systemOneFS distributed file systemThe OneFS file system is a distributed networked file system designed by Isilon Systems for use in its Isilon IQ storage appliances. OneFS is a FreeBSD variant and utilizes zsh as its shell...
from Isilon. BSD based OS on dedicated Intel based hardware, serving NFS v3 and SMB/CIFS to WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, Mac OSMac OSMac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...
, LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
and other UNIXUnixUnix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
clients under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - Panasas ActiveScale File System (PanFS) from PanasasPanasasPanasas, Inc., is a private, multinational computer storage company based in Sunnyvale, California. It specializes in high-performance scale-out network-attached storage optimized for Linux clusters.- History :...
uses object storage deviceObject storage deviceAn Object-based Storage Device is a computer storage device, similar to disk storage but working at a higher level. Instead of providing a block-oriented interface that reads and writes fixed sized blocks of data, an OSD organizes data into flexible-sized data containers, called objects...
s. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - PeerFS from Radiant Data Corporation focus on high availabilityHigh availabilityHigh availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period....
and high performance and uses peer-to-peerPeer-to-peerPeer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads among peers. Peers are equally privileged, equipotent participants in the application...
replication with multiple sources and targets. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - TerraGrid Cluster File System from Terrascale Technologies Inc implements on demand cache coherencyCache coherencyIn computing, cache coherence refers to the consistency of data stored in local caches of a shared resource.When clients in a system maintain caches of a common memory resource, problems may arise with inconsistent data. This is particularly true of CPUs in a multiprocessing system...
and uses industrial standard iSCSIISCSIIn computing, iSCSI , is an abbreviation of Internet Small Computer System Interface, an Internet Protocol -based storage networking standard for linking data storage facilities. By carrying SCSI commands over IP networks, iSCSI is used to facilitate data transfers over intranets and to manage...
and a modified version of the XFSXFSXFS is a high-performance journaling file system created by Silicon Graphics, Inc. It is the default file system in IRIX releases 5.3 and onwards and later ported to the Linux kernel. XFS is particularly proficient at parallel IO due to its allocation group based design...
file system. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under a proprietary softwareProprietary softwareProprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
license. - XtreemFSXtreemFSXtreemFS is an object-based, distributed file system for wide area networks. The file system replicates objects for fault tolerance and caches metadata and data to improve performance over high-latency links. SSL and X.509 certificates support make XtreemFS usable over public networks...
http://www.xtreemfs.com is a free and open-source (GPL) cross-platformCross-platformIn computing, cross-platform, or multi-platform, is an attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms...
file system for wide area networks. It replicates the data for fault tolerance and caches metadata and data to improve performance over high-latency links. SSLTransport Layer SecurityTransport Layer Security and its predecessor, Secure Sockets Layer , are cryptographic protocols that provide communication security over the Internet...
and X.509X.509In cryptography, X.509 is an ITU-T standard for a public key infrastructure and Privilege Management Infrastructure . X.509 specifies, amongst other things, standard formats for public key certificates, certificate revocation lists, attribute certificates, and a certification path validation...
certificates support makes XtreemFS usable over public networks. It supports also Striping for usage in a clusterCluster (computing)A computer cluster is a group of linked computers, working together closely thus in many respects forming a single computer. The components of a cluster are commonly, but not always, connected to each other through fast local area networks...
. - Chiron FSChiron FSChiron Filesystem is a fault-tolerant replication file system.Chiron FS is a FUSE based filesystem that implements replication at the filesystem level like RAID 1 does at the device level...
is a fuseFilesystem in UserspaceFilesystem in Userspace is a loadable kernel module for Unix-like computer operating systems that lets non-privileged users create their own file systems without editing kernel code...
-based, transparent replication file system, layering on an existing file system and implementing at the file system level what RAIDRAIDRAID is a storage technology that combines multiple disk drive components into a logical unit...
1 does at the device level. A notably convenient consequence is the possibility of picking single target directories, without the need of replicating entire partitions. (The project has no visible activity after 2008, a status request in Oct. 2009 in the chironfs-forum is unanswered)
In development:
- PlasmaFS is a free and open-source (GPL) userspace filesystem focusing on data safety and security. PlasmaFS provides a transactional API which is accessible over a SunRPC-based protocol. PlasmaFS can also be mounted as NFS volume, and is POSIX-compliant. Both data and metadata are replicated.
- WebDFSWebDFSAn Open Source Distributed File System that can be used behind an HTTP server to implement a highly scalable DFS for storing images, etc.webDFS is mostly based on the algorithms described in these papers :...
An Open Source scalable, decentralized file store similar to MogileFS in function and purpose. Uses HTTP as the transport. Data is automatically and optimally re-arranged to accommodate the addition of new resources. The lack of central meta data management greatly simplifies deployment and use. - CephCeph-External links:* *...
from University of California, Santa CruzUniversity of California, Santa CruzThe University of California, Santa Cruz, also known as UC Santa Cruz or UCSC, is a public, collegiate university; one of ten campuses in the University of California...
which utilized entire block devices. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
under the LGPLGNU Lesser General Public LicenseThe GNU Lesser General Public License or LGPL is a free software license published by the Free Software Foundation . It was designed as a compromise between the strong-copyleft GNU General Public License or GPL and permissive licenses such as the BSD licenses and the MIT License...
. Merged for Linux kernel 2.6.34. - zFSZFS (IBM file system)zFS refers to two different IBM file systems:* zFS most often refers to z/OS Distributed File Service zSeries File System, the newest POSIX-style hierarchical file system for IBM's z/OS operating system, a successor to that operating system's HFS...
from IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
(not to be confused with ZFSZFSIn computing, ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include data integrity verification against data corruption modes , support for high storage capacities, integration of the concepts of filesystem and volume management,...
from Sun MicrosystemsSun MicrosystemsSun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
or the zFS file system provided with IBM's z/OSZ/OSz/OS is a 64-bit operating system for mainframe computers, produced by IBM. It derives from and is the successor to OS/390, which in turn followed a string of MVS versions.Starting with earliest:*OS/VS2 Release 2 through Release 3.8...
operating system) focus on cooperative cache and distributed transactions and uses object storage deviceObject storage deviceAn Object-based Storage Device is a computer storage device, similar to disk storage but working at a higher level. Instead of providing a block-oriented interface that reads and writes fixed sized blocks of data, an OSD organizes data into flexible-sized data containers, called objects...
s. Under development and not freely available. - Hadoop Distributed File SystemHadoopApache Hadoop is a software framework that supports data-intensive distributed applications under a free license. It enables applications to work with thousands of nodes and petabytes of data...
- free GoogleFS clone produced by Apache. http://hadoop.apache.org/ - HAMMER/ANVIL by Matt DillonMatt Dillon (computer scientist)Matthew Dillon is a computer scientist living in Berkeley, California. He is best known for his contributions to FreeBSD and for starting the DragonFly BSD project....
- OASIS from ETRIETRIThe Electronics and Telecommunications Research Institute, Korea is a government-backed research institute in Daedeok Science Town in Daejeon, Republic of Korea...
. Very similar to the LustreLustre (file system)Lustre is a massively parallel distributed file system, generally used for large scale cluster computing. The name Lustre is a portmanteau word derived from Linux and cluster...
or PanasasPanasasPanasas, Inc., is a private, multinational computer storage company based in Sunnyvale, California. It specializes in high-performance scale-out network-attached storage optimized for Linux clusters.- History :...
. Available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
via. special technology transfer program provided by ETRI. - GLORY-FS also from ETRIETRIThe Electronics and Telecommunications Research Institute, Korea is a government-backed research institute in Daedeok Science Town in Daejeon, Republic of Korea...
. Very similar to the Google File System or HadoopHadoopApache Hadoop is a software framework that supports data-intensive distributed applications under a free license. It enables applications to work with thousands of nodes and petabytes of data...
, but it is fully POSIX compliant. It is specially optimized for large scale web 2.0 content services. Version 2.5 is available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
via. special technology transfer program provided by ETRI. WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
version is under development. - parallax
- PNFS (Parallel NFS) - Clients available for LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
and OpenSolarisOpenSolarisOpenSolaris was an open source computer operating system based on Solaris created by Sun Microsystems. It was also the name of the project initiated by Sun to build a developer and user community around the software...
and back-ends from PanasasPanasasPanasas, Inc., is a private, multinational computer storage company based in Sunnyvale, California. It specializes in high-performance scale-out network-attached storage optimized for Linux clusters.- History :...
, EMCEMC CorporationEMC Corporation , a Financial Times Global 500, Fortune 500 and S&P 500 company, develops, delivers and supports information infrastructure and virtual infrastructure hardware, software, and services. EMC is headquartered in Hopkinton, Massachusetts, USA.Former Intel executive Richard Egan and his...
Highroad and IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
GPFS - Coherent Remote File System (CRFSCRFSCRFS is a network file system protocol by Zach Brown formerly of Oracle intended to leverage the Btrfs architecture to gain higher performance than existing protocols and to expose Btrfs features such as snapshots to remote clients...
) - requires BtrfsBtrfsBtrfs is a GPL-licensed copy-on-write file system for Linux.Development began at Oracle Corporation in 2007.... - Parallel Optimized Host Message Exchange Layered File System (POHMELFSPOHMELFSPOHMELFS is an asynchronous cache coherent distributed file system developed by Russian Linux hacker Evgeniy Polyakov...
) and Distributed STorage (DST). POSIX compliant, added to Linux kernel 2.6.30 - Sector http://sector.sourceforge.net from National Center for Data MiningNational Center for Data MiningThe National Center for Data Mining is a center of the University of Illinois at Chicago , established in 1998 to serve as a resource for research, standards development, and outreach for high performance and distributed data mining and predictive modeling.NCDM won the High Performance Bandwidth...
. Sector is a high performance, scalable, and secure distributed file system. Available under Apache License 2.0Apache LicenseThe Apache License is a copyfree free software license authored by the Apache Software Foundation . The Apache License requires preservation of the copyright notice and disclaimer.... - StarFS from CDNetworksCDNetworksCDNetworks founded in 2000, is a full service content delivery network , with increasing business in the United States.-Content delivery services:...
. The StarFS is a global storage platform which supports virtualization of distributed file system and event-driven file synchronization with remote StarFS clusters. - Unilium http://unilium.com provides a decentralized, versioning file system stored in content addressable storage, whose data may be hosted across heterogeneous data storage nodes.
Peer-to-peer file systems
- CFS is a read-only file system based on the Chord DHT
- CleversafeCleversafeCleversafe, Inc. is a privately held company based in the United States which is pioneering Dispersed Storage technology and software. Dispersed storage is a technology that uses erasure codes to split data into multiple slices, each of which is then stored to an independent storage appliance via...
uses Cauchy Reed-Solomon Information Dispersal Algorithms (IDAs) to separate data into unrecognizable slices and distribute them, via secure Internet connections, to multiple storage locations. - InfinitInfinitInfinit is a file system software that enables users to store, share and access their files in a safe way, from any Internet-connected device.-Features:...
is a large-scale peer-to-peer file system developed in C++ which enables users to both reliably and securely store their files in a location-independent and replicated way; and to share files with a controlled set of users, friends etc. - Ivy is a multi-user read/write peer-to-peer file system. Ivy has no centralized or dedicated components, and it provides useful integrity properties without requiring users to fully trust either the underlying peer-to-peer storage system or the other users of the file system.
- Pastis file system is a French peer-to-peer file system developed in Java
- ColonyFS emphasises anonymity, security and dependability, is written in Java and C#, and is released under the GPL
Special purpose file systems
- archfs (archive)
- aufsAufsaufs implements a union mount for Linux file systems.Developed by Junjiro Okajima in 2006 aufs is a complete rewriting of the earlier UnionFS...
an enhanced version of UnionFSUnionFSUnionFS is a filesystem service for Linux, FreeBSD and NetBSD which implements a union mount for other file systems. It allows files and directories of separate file systems, known as branches, to be transparently overlaid, forming a single coherent file system...
stackable unification file system - AXFSAXFSAXFS is a compressed read-only file system for Linux, initially developed at Intel, and now maintained at Numonyx. It was designed to utilize execute in place alongside compression aiming to reduce boot and program load times, while retaining a small memory footprint for embedded devices...
(small footprint compressed read-only, with XIP) - Barracuda WebDAV plug-in. Secure Network File Server for embedded devices.
- Boot File SystemBoot File SystemThe Boot File System was used on UnixWare to store files necessary to its boot process....
was used on UnixWare to store files necessary to its boot process. - Cascade File SystemCascade (software)Cascade is a proprietary software configuration management tool suite developed by Conifer Systems LLC. It includes:* Cascade File System, a file system driver that exposes a Subversion or Perforce repository as a modifiable directory tree in the user's file system.* Cascade Proxy, a proxy server...
– provides file system access to Subversion and PerforcePerforcePerforce is a commercial, proprietary, centralized revision control system developed by Perforce Software, Inc.-Architecture:Perforce is a client/server system.The server manages a central database and a master repository of file versions....
repositories and caches their contents locally - cdfsCDFSCDfs is a virtual Linux file system that provides access to individual data and audio tracks on Compact Discs. A Compact Disc mounted with the "CDfs" driver appears as a collection of files, each representing a single track...
(reading and writing of CDs) - Compact Disc File SystemCompact Disc File SystemThe Compact Disc File System was a file system for read-only and write-once CDROMs developed by Simson Garfinkel and J. Spencer Love at the MIT Media Lab between 1985 and 1986. The file system provided for the creation, modification, renaming and deletion of files and directories on a write-once...
(reading and writing of CDs; experimental) - cfsCFS (Compact File Set file format)Compact File Set is an open archive file format and software distribution container file format.- Overview :The Compact File Set is an open archive file format and software distribution container file format....
(caching) - cvsfs (presents the CVS contents as mountable file system).
- Dokan LGPL FUSE for Windows analog
- compFUSEd (overlay transparent read-write compression, FUSE based)
- FuseCompress (overlay transparent read-write compression, FUSE based)
- CramfsCramfsThe compressed ROM file system is a free read-only Linux file system designed for simplicity and space-efficiency. It is mainly used in embedded systems and small-footprint systems....
(small footprint compressed read-only) - Cromfs is a user-space (FUSE based) read-only filesystem using an efficient LZMA compression algorithm.
- Davfs2Davfs2In computer networking davfs2 is a Linux tool for connecting to WebDAV shares as though they were local disks. It an open-source GPL-licensed file system for mounting WebDAV servers. For communicating with the kernel, davfs2 can either use the FUSE file system API, or the Coda network file system...
(WebDAVWebDAVWeb-based Distributed Authoring and Versioning is a set of methods based on the Hypertext Transfer Protocol that facilitates collaboration between users in editing and managing documents and files stored on World Wide Web servers...
)- - FreenetFreenetFreenet is a decentralized, censorship-resistant distributed data store originally designed by Ian Clarke. According to Clarke, Freenet aims to provide freedom of speech through a peer-to-peer network with strong protection of anonymity; as part of supporting its users' freedom, Freenet is free and...
– Decentralized, censorship-resistant - FTPFSFTPFSFTPFS refers to file systems that support access to a File Transfer Protocol server through standard file system application programming interfaces ....
/CurlFtpFSCurlFtpFSCurlFtpFS is a filesystem for accessing FTP hosts based on FUSE and libcurl, which offers the following features amongst others:* SSLv3 and TLSv1 support;* the ability to connect through tunneling HTTP proxies;...
(ftp access) - GmailFSGmailFSGmailFS is a virtual file system originally developed by Richard Jones that uses a Gmail e-mail account for storage. GmailFS is written for Linux, but Windows and Mac OS X ports exist too. It originally was based on underlying SMTP and POP3 interation with gmail...
(Google Mail File System) - lnfsLnfslnfs is a Plan 9 file system enabling use of long filenames on filesystems which do not support them. Similar to the UMSDOS file system for Linux....
(long names) - mhddfs - Join several filesystems together to form a single larger one
- mini fo (The mini fanout overlay file system) – Redirects modifying operations to a writeable location called "storage directory", and leaving the original data in the "base directory" untouched. When reading, the file system merges the modified and original data so that only the newest versions will appear. Most prominently used in OpenWrtOpenWrtOpenWrt is a Linux distribution primarily targeted at routing on embedded devices. It comprises a set of about 2000 software packages, installed and uninstalled via the opkg package management system. OpenWrt can be configured using the command-line interface of BusyBox ash, or the web interface...
- MVFSMultiVersion File SystemMVFS is a virtual file system which displays specific versions of data stored in ClearCase. In particular, it supports dynamic views which can show an arbitrary combination of local and remote files....
– MultiVersion File System, proprietary, used by Rational ClearCaseRational ClearCaseThe Rational ClearCase family consists of several software tools for supporting software configuration management of source code and other software development assets. It is developed by the Rational Software division of IBM...
. - nntpfs (netnews)
- ParFiSys (Experimental parallel file system for massively parallel processing)
- plumber (Plan 9) (interprocess communication – pipes)
- pramfs - Protected and Persistent RAM Filesystem
- RAIF Redundant Array of Independent Filesystems - stackable RAID-like file system
- romfsRomfsIn computing, romfs is an extremely simple file system lacking many features, intended for burning important files onto an EEPROM. It is available on Linux, and possibly other Unix-like systems....
- SODA: a Lease-based Consistent Distributed File System - (early 1990s)
- SquashFSSquashFSSquashFS is a compressed read-only file system for Linux. SquashFS compresses files, inodes and directories, and supports block sizes up to 1 MB for greater compression...
(compressed read-only) - SysmanFS (based on FUSE, a virtual file system for cluster system management)
- tmpfsTMPFStmpfs is a common name for a temporary file storage facility on many Unix-like operating systems. It is intended to appear as a mounted file system, but stored in volatile memory instead of a persistent storage device...
in-memory temporary file system (on Linux platforms). - UMSDOSUMSDOSLinux has several filesystem drivers for the File Allocation Table filesystem format. These are commonly known by the names used in the mount command to invoke particular drivers in the kernel: msdos, vfat, and umsdos....
- FAT file system extended to store permissions and metadata, used for Linux - UnionFSUnionFSUnionFS is a filesystem service for Linux, FreeBSD and NetBSD which implements a union mount for other file systems. It allows files and directories of separate file systems, known as branches, to be transparently overlaid, forming a single coherent file system...
- stackable unification file system, which can appear to merge the contents of several directories (branches), while keeping their physical content separate - VentiVentiVenti is a network storage system that permanently stores data blocks. A 160-bit SHA-1 hash of the data acts as the address of the data...
- Plan 9 de-duplicated storage used by FossilFossil (file system)Fossil is the default file system in Plan 9 from Bell Labs. It serves the network protocol 9P and runs as a user space daemon, like most Plan 9 file servers. Fossil is different from most other file systems due to its snapshot/archival feature. It can take snapshots of the entire file system on...
. - wikifs (Plan 9) (wiki wikiWikiA wiki is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor. Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include...
) - WDK.VFS - SiteAdmin CMS Virtual File System introduced by Evgenios Skitsanos
- Datalight Reliance - transactional file system for 32-bit embedded systems from DatalightDatalightDatalight is a privately held software company specializing in data management for embedded devices, particularly mobile phones. The company was founded in 1983 by Roy Sherrill, and is headquartered in Bothell, Washington.-Overview and history:...
, Inc. - ERTFS ProPlus64 - it comes with integrated Failsafe operation, it contains a default journaling mode.
- WBFSWBFSWBFS, or Wii Backup File System, is a file system developed by Wii homebrew coders kwiirk and Waninkoko. It uses Waninkoko's cIOS and works by creating a WBFS partition on a SD or USB device. A Wii homebrew application may then be run to dump a Wii game to the partition...
- Wii Backup FileSystem - whefs - WanderingHorse.net Embedded Filesystem is an open source C library implementing an embedded/embeddable filesystem.
Pseudo- and virtual file systems
- devfs
- procfsProcfsprocfs 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 method for dynamically accessing process data held in the kernel than traditional...
– pseudo-file system, used to access kernel information about processes - specfsSpecfsOn Unix-like computer systems, specfs is short for special filesystem. This is not a physical or network file system by any means and it does not have a mount point either. This simply an FS layer to access device special files, which are hosted in any of the regular filesystems....
(Special File System for device files ) - sysfsSysfsSysfs is a virtual file system provided by Linux 2.6. Sysfs exports information about devices and drivers from the kernel device model to user space, and is also used for configuration...
(LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
) - WinFSWinFSWinFS is the code name for a cancelled data storage and management system project based on relational databases, developed by Microsoft and first demonstrated in 2003 as an advanced storage subsystem for the Microsoft Windows operating system, designed for persistence and management of...
- Windows Future Storage, was planned as the successor to NTFS for Windows Vista.
Encrypted file systems
- eCryptfs - a stacked cryptographic file system in the Linux kernel since 2.6.19
- Secure Shell File SystemSSHFSIn computing, SSHFS is a filesystem client to mount and interact with directories and files located on a remote server or workstation...
(SSHFS) - locally mount a remote directory on a server using only a secure shellSecure ShellSecure Shell is a network protocol for secure data communication, remote shell services or command execution and other secure network services between two networked computers that it connects via a secure channel over an insecure network: a server and a client...
login. - EncFSEncFSEncFS is a Free FUSE-based cryptographic filesystem that transparently encrypts files, using an arbitrary directory as storage for the encrypted files....
, GPL Encrypted file systemDisk encryption softwareTo protect confidentiality of the data stored on a computer disk a computer security technique called disk encryption is used. This article discusses software that is used to implement the technique...
in user-space - Rubberhose filesystemMaruTukkuIn computing, rubberhose is a deniable encryption archive containing multiple file systems whose existence can only be verified using the appropriate cryptographic key.- Name and history :...
- PhoneBookFS
- Solid File System - (SolFS) cross-platform single-file virtual file system with encryption and compression
- EFSEncrypting File SystemThe Encrypting File System on Microsoft Windows is a feature introduced in version 3.0 of NTFS that provides filesystem-level encryption...
– Encrypted file system for Microsoft WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
systems and AIXAIX operating systemAIX AIX AIX (Advanced Interactive eXecutive, pronounced "a i ex" is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms...
. An extension of NTFSNTFSNTFS is the standard file system of Windows NT, including its later versions Windows 2000, Windows XP, Windows Server 2003, Windows Server 2008, Windows Vista, and Windows 7.... - FSFS - Fast Secure File System Project Home page
- ZFSZFSIn computing, ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include data integrity verification against data corruption modes , support for high storage capacities, integration of the concepts of filesystem and volume management,...
Encryption Support Project Home page
Files 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)
- VFS Virtual Filesystem
- Callback File System – SDK that lets developers create installable virtual file systems for Windows in user mode
See also
- Shared file access
- Comparison of file systemsComparison of file systems-General information:-Limits:-Metadata:-Features:-Allocation and layout policies:-Supporting operating systems:-See also:* Comparison of archive formats* Comparison of file archivers* List of archive formats* List of file archivers...
- Filing OSID
- Computer storageComputer storageComputer data storage, often called storage or memory, refers to computer components and recording media that retain digital data. Data storage is one of the core functions and fundamental components of computers....