extent (noun)

the point or degree to which something extends

"the extent of the damage"; "the full extent of the law"; "to a certain extent she was right"

extent (noun)

the distance or area or volume over which something extends

"the vast extent of the desert"; "an orchard of considerable extent"

extent (Noun)

A range of values or locations.

extent (Noun)

The space, area, volume, etc., to which something extends.

extent (Noun)

A contiguous area of storage in a file system.

Extent

An extent is a contiguous area of storage in a computer file system, reserved for a file. When a process creates a file, file-system management software allocates a whole extent. When writing to the file again, possibly after doing other write operations, the data continues where the previous write left off. This reduces or eliminates file fragmentation and possibly file scattering too. An extent-based file system need not require limiting each file to a single, contiguous extent. The following systems support extents: ⁕ASM - Automatic Storage Management - Oracle's database-oriented filesystem. ⁕BFS - BeOS, Zeta and Haiku operating systems. ⁕Btrfs - GPL'd extent based file storage for Linux. ⁕Ext4 - Linux filesystem. ⁕Files-11 - Digital Equipment Corporation OpenVMS filesystem. ⁕HFS and HFS Plus - Hierarchical File System - Apple Macintosh filesystems. ⁕HPFS - High Performance File Syzstem - OS/2 and eComStation. ⁕JFS - Journaled File System - Used by AIX, OS/2/eComStation and Linux operating systems.