Unix File System

The UNIX File System ( UFS ) is a file system whose development began in early 1980 by Bill Joy under the name UFS loosely based on the data structures of the Unix Version 6 file system. Two years later, after the file system has already been used at some universities, Marshall Kirk McKusick came to the project and devote himself mainly improved Allozierungsmechanismen. At this time also appeared the first time the name Fast File System. With UNIX System V version 4 UFS has also been adopted in the AT & T version of UNIX and solved the file system of UNIX version 6 as a default file system from.

Variants

Berkeley Fast File System ( FFS)

Is used, the UFS is currently in the variant Berkeley Fast File System from various BSD derivatives such as FreeBSD, NetBSD, and OpenBSD, and Solaris and NeXTStep. On Linux and Mac OS X, it is also available, but not part of the standard. By design, the file system resulting in the Linux ext2 project is a descendant of UFS.

Solaris offers from version 7 on an option that implements a journaling in UFS ( prior to Solaris 7 journaling could be activated via trans - Devices Solstice DiskSuite ). Among the BSD operating systems there is the Soft Updates extension, an efficient method for writing the metadata that keeps the file system in a consistent state. Also supports NetBSD since mid-2008 metadata journaling. NetBSD 5.0 was the first stable version with support for metadata journaling, where it was, however, still listed as a preview.

UFS2

UFS2 is an extension to UFS and was introduced in FreeBSD 5.x. UFS2 mainly brings the following changes:

• Support for file systems larger than 1TB.
• It is possible to create the file system snapshots.
• The " file system check " after a system crash takes place in the background. Thus, the time required for booting is very reduced for large file systems.
• Additional file attributes were added, which include, inter alia, a POSIX - compliant implementation of access control lists.