File systems

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From Wikipedia:

A file system (or filesystem) 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(s) which contain it. A file system organizes data in an efficient manner and is tuned to the specific characteristics of the device.

Individual drive partitions can be setup using one of the many different available filesystems. Each has its own advantages, disadvantages, and unique idiosyncrasies. A brief overview of supported filesystems follows; the links are to Wikipedia pages that provide much more information.

Before being formatted, a drive should be partitioned unless the whole disk is being added to a ZFS storage pool in which case the entire drive is formatted without any partitions.

Native PacBSD file systems

  • UFS2 — UFS2 is the modernized and improved version of the Unix File System (UFS) originally developed by Computer Science Research Group (CSRG) and introduced in 4.2BSD
  • ZFSCombined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include protection against data corruption, support for high storage capacities, integration of the concepts of filesystem and volume management, snapshots and copy-on-write clones, continuous integrity checking and automatic repair, RAID-Z and native NFSv4 ACLs.

Supported Linux File systems

  • ext2Second Extended Filesystem is an established, mature GNU/Linux filesystem that is very stable. A drawback is that it does not have journaling support or barriers. Lack of journaling can result in data loss in the event of a power failure or system crash. It may also be not convenient for root (/) and /home partitions because file-system checks can take a long time. Support for ext2 is provided by the ext2fs(5) driver, which has been available since FreeBSD 2.2 and was rewrittin in FreeBSD 9.0 and relicensed from GPL to BSD.

Note: This driver can also be used to access ext3 and ext4 file systems. However, ext3 journaling, extended attributes, and inodes greater than 128-bytes are not supported. The ext2fs driver provides full read and write support for ext2 and ext3, while only offering read support for ext4.
  • ReiserFS -- Hans Reiser's high-performance journaling FS (v3) uses a very interesting method of data throughput based on an unconventional and creative algorithm. ReiserFS is touted as very fast, especially when dealing with many small files. ReiserFS is fast at formatting, yet comparatively slow at mounting. Quite mature and stable. ReiserFSv3 is not being actively developed at this time. Support for ReiserFS is provided by the reiserfs(5) driver. PacBSD only offers read-only support for ReiserFS.

FUSE-based file systems

See also