Difference Between ZFS and UFS

ZFS vs. UFS

ZFS is a combined file system and logical volume manager. It includes support for high storage capacities, integration of concepts of file systems and volume management, snapshots and copy on write clones (that is, an optimization strategy that allows callers who ask for resources that are indistinguishable to be given pointers to the same resource), continuous integrity checking and automatic repair, RAID -Z, and native NFSv4 ACLs. It is an open source software that is licensed under the Common Development and Distribution License (or CDDL).

The Unix File System (also known as UFS) is a file system used exclusively with Unix, and all Unix-like operation systems. It has been known as the Berkeley Fast File System, and is a removed descendant of the original file system used in Version 7 Unix.

ZFS is made up of a plethora of features and components. The storage pool of ZFS is known as a zpool. It is constructed of virtual devices (or vdevs) which are constructed of block devices – files, hard drive partitions or entire drives (recommended). As such, vdevs are often times considered to be a group of hard drives. A ZFS capacity is rather large in comparison to standard file systems. It is a 128 bit file system, enabling it to address 18 quintillion times more data than 64 bit systems. The limitations found in ZFS are designed specifically to be large enough to never be encountered (within the known limits of physics, and the number of atoms in the earth’s crust to construct a storage device of this magnitude). The other features include a copy on write transactional model, snapshots and clones, dynamic striping, variable block sizes, lightweight file system creation, cache management, adaptive endianness, and deduplication (to name a few of the more common features).

UFS is composed of a variety of parts and components. There are a few blocks at the very beginning of the partition that are reserved for boot blocks – these must be initialized separately from the file system. There is a superblock, which contains a magic number identifying it is a UFS file system, as well as other numbers that are vital to the description of the file system’s geometry, statistics, and behavioral tuning parameters. There is a collection of cylinder groups – each of which that has a backup copy of the superblock, a cylinder group header (with statistics, free lists, etc.), a number of inodes that are numbered sequentially and contain file attributes, and a number of data blocks.

Summary:

1. ZFS is an open source software combined file system that supports high storage capacities; UFS is a file system unique to Unix, and is a removed descendant of the original Version 7 Unix file system.

2. ZFS has a capacity that is so large that any limitations set on it are never reached; UFS contains a collection of cylinder groups.

Sharing is caring!