The following lists identify, characterize and link to more thorough information on computerfile systems.
Many older operating systems support only their one "native" file system, which does not bear any name apart from the name of the operating system itself. Examples of such include the CP/M file system and the Apple DOS file system. These unnamed file systems don't appear in the following list.
Disk file systems are usually block-oriented. Files in a block-oriented file system are sequences of blocks, often featuring fully random-access read, write, and modify operations.
ADFS ? Acorn's Advanced Disc filing system, successor to DFS.
CBMFS ? The filesystem used on most Commodore 64-compatible floppy drives including the venerable 1541.
CMDFS ? A filesystem extension added to CBMFS by Creative Micro Designs, for use in their 3.5 inch floppy drives, RAM disks, and hard drive controllers.
DTFS ? Desktop File System, featuring file compression, used by SCO OpenServer
DOS 3.x - Original floppy operating system and file system developed for the Apple II
FAT ? File Allocation Table, used on DOS and Microsoft Windows, 12-, 16- and 32-bit table depths.
VFAT ? Version of Microsoft Windows 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 Windows FAT system that is used on the original Xbox console.
FFS (Amiga) ? Fast File System, used on Amiga systems. This FS has evolved over time. Now counts FFS1, FFS Intl, FFS DCache, FFS2.
Files-11 ? OpenVMS file system; also used on some PDP-11 systems; supports record-orientated files
HFS ? Hierarchical File System, used on older Mac OS systems. Successor to Macintosh File System (MFS) and predecessor to HFS+; not to be confused with IBM's HFS provided with z/OS
HFS Plus ? Updated version of HFS, used on newer Mac OS systems. Also called HFS+. Recent versions allow journaling.
NSS ? Novell Storage Services. This is a new 64-bit journaling file system using a balanced tree algorithm. Used in NetWare versions 5.0-up and recently ported to Linux.
OneFS - One File System. This is a fully-journaled, distributed file system used by Isilon. OneFS uses FlexProtect and Reed-Solomon encodings to support up to four simultaneous disk failures.
OFS ? Old File System, on Amiga. Good for floppies, but fairly useless on hard drives.
PFS ? and PFS2, PFS3, etc. Technically interesting file system available for the Amiga, performs very well under a lot of circumstances. Very simple and elegant.
ProDOS - Operating system and file system successor to Apple's DOS 3.x, used with the Apple II series including the IIgs
Qnx4fs - File system that is used in QNX version 4 and 6.
Qnx6fs - New copy-on-write file system presented in QNX 6.4.0 and used as default since 6.4.1.
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 GEOS.
WAFL ? Write Anywhere File Layout. High performance, log-structured like file system. WAFL uses RAID-DP to protect against multiple disk failures, and NVRAM for transaction log replays. Used on NetApp systems
File systems optimized for flash memory / solid state media
Solid state media, like flash memory, are similar to disks in their interfaces, but have different problems. While eliminating seek times, they require special handling such as wear leveling and different error detection and correction algorithms.
ETFS - Embedded Transactional File System. Designed primarily for NAND devices by QNX Software Systems.
exFAT - Microsoft proprietary system intended for flash drives but often called FAT64 - limit of 264 bytes (16 Exabytes)
OneFS - OneFS is a file system utilized by Isilon. It supports selective placement of meta-data directly onto flash SSD.
Segger Microcontroller SystemsemFile - File system for deeply embedded applications which supports both NAND and NOR flashes. Wear leveling, fast read and write, and very low RAM usage.
TFAT ? A transactional version of the FAT filesystem.
TrueFFS - Internal file system for SSDs, implementing error correction, bad block re-mapping and wear levelling.
Write Anywhere File Layout - WAFL is an internal file system utilized by NetApp within their DataONTAP OS, originally optimized to utilize non-volatile DRAM
YAFFS ? A Log structured file system designed for NAND flash, but also used with NOR flash.
Record-oriented file systems
In record-oriented file systems files are stored as a collection of records. They are typically associated with mainframe and minicomputer 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 databases than with other file systems.
Files-11 ? early versions were record-oriented; support for "streams" was added later
Shared disk file systems (also called shared storage file systems, SAN file system 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.
Self-certifying File System (SFS), a global network file system designed to securely allow access to file systems across separate administrative domains.
Server Message Block (SMB) originally from IBM (but the most common version is modified heavily by Microsoft) 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 availability and offline (disconnected) operation.
Coda from Carnegie Mellon University 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 Linux under the GPL.
Moose File System (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 FreeBSD, Linux, Solaris and MAC OS X.
Tahoe-LAFShttp://allmydata.org/trac/tahoe is an open source secure, decentralized, fault-tolerant filesystem utilizing encryption as the basis for a least-authority replicated design.
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.
Fraunhofer Parallel File System (FhGFS) from the Fraunhofer Society Competence Center for High Performance Computing. Available free of charge for Linux under a proprietary license. (High availability features are on the roadmap, currently only local file locking is supported)
Lustre is a POSIX-compliant, high-performance filesystem originally developed by Cluster File Systems, and later acquired by Sun Microsystems in 2007. Lustre has high availability via storage failover, but multi-server RAID1 or RAID5 is still in the roadmap for future versions. Freely available for Linux under GPL. Versions for Solaris and Windows are also under development.
Parallel Virtual File System (PVFS, PVFS2). Developed to store virtual system images, with a focus on non shared writing optimizations. Available for Linux under GPL.
Starfish is a POSIX-compatible, N-way redundant file system created by Digital Bazaar Inc. and published under a pseudo-open source license. Available for Linux and Mac OS. Windows support is available via Samba.
dCache by Fermilab and DESY. 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 Exanet. 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 Windows, Mac OS, Linux and other UNIX clients. Available under a proprietary software license.
General Parallel File System (GPFS) from IBM. Support replication between attached block storage. Available for AIX, Linux and Windows. Symmetric or asymmetric (configurable). (proprietary)
GlusterFS 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.
MogileFS from Danga Interactive is not POSIX compliant, uses a flat namespace, application level, uses MySQL for metadata and HTTP for transport. Available for Linux (but may be ported) under GPL.
XtreemFShttp://www.xtreemfs.com is a free and open-source (GPL) cross-platform 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. SSL and X.509 certificates support makes XtreemFS usable over public networks. It supports also Striping for usage in a cluster.
In development:
WebDFS 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.
OASIS from ETRI. Very similar to the Lustre or Panasas. Available for Linux via. special technology transfer program provided by ETRI.
GLORY-FS also from ETRI. Very similar to the Google File System or Hadoop, but it is fully POSIX compliant. It is specially optimized for large scale web 2.0 content services. Version 2.5 is available for Linux via. special technology transfer program provided by ETRI. Windows version is under development.
Infinit 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.
Ivyhttp://pdos.csail.mit.edu/ivy/osdi02.pdf 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
UMSDOS – FAT file system extended to store permissions and metadata, used for Linux.
UnionFS – stackable unification file system, which can appear to merge the contents of several directories (branches), while keeping their physical content separate
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 modifed and original data so that only the newest versions will appear.
WinFS - Windows Future Storage, currently still in beta and in use internally at Microsoft, it is planned as the successor to NTFS. It is uncertain whether it will be available as a service pack for Windows Vista or if it will be shipped with a later version of Windows, or if it is even abandoned at all.
Encrypted file systems
eCryptfs - a stacked cryptographic filesystem in the Linux kernel since 2.6.19
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