AXFS
Encyclopedia
AXFS is a compressed
Data compression
In computer science and information theory, data compression, source coding or bit-rate reduction is the process of encoding information using fewer bits than the original representation would use....

 read-only
File system permissions
Most current file systems have methods of administering permissions or access rights to specific users and groups of users. These systems control the ability of the users to view or make changes to the contents of the filesystem....

 file system
File system
A file system 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 which contain it. A file system organizes data in an efficient manner and is tuned to the...

 for Linux, initially developed at Intel, and now maintained at Numonyx
Numonyx
Numonyx is a semiconductor company making flash memories, which was founded on March 31, 2008 by Intel Corporation, STMicroelectronics and Francisco Partners. It was acquired by Micron Technology on February 9, 2010....

. It was designed to utilize execute in place
Execute in place
In computer science, execute in place is a method of executing programs directly from long term storage rather than copying it into RAM. It is an extension of using shared memory to reduce the total amount of memory required....

 (XIP) alongside compression aiming to reduce boot
Boot
A boot is a type of footwear but they are not shoes. Most boots mainly cover the foot and the ankle and extend up the leg, sometimes as far as the knee or even the hip. Most boots have a heel that is clearly distinguishable from the rest of the sole, even if the two are made of one piece....

 and program load times, while retaining a small memory footprint
Memory footprint
Memory footprint refers to the amount of main memory that a program uses or references while running.This includes all sorts of active memory regions like code, static data sections , heap, as well as all the stacks, plus memory required to hold any additional data structures, such as symbol...

 for embedded devices. This is achieved by mixing compressed and uncompressed pages in the same executable file. AXFS is free software
Free software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...

 (licensed under the GPL
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....

).

Cramfs
Cramfs
The compressed ROM file system is a free read-only Linux file system designed for simplicity and space-efficiency. It is mainly used in embedded systems and small-footprint systems....

 is another read-only compressed file system that supports XIP (with patches), however it uses a strategy of decompressing entire files, whereas AXFS supports XIP with page granularity.

See also

  • Squashfs
    SquashFS
    SquashFS is a compressed read-only file system for Linux. SquashFS compresses files, inodes and directories, and supports block sizes up to 1 MB for greater compression...

     is another read-only compressed file system
  • Cloop
    Cloop
    The compressed loopback device or cloop is a module for the Linux kernel. It adds support for transparently decompressed, read-only block devices. It is not a compressed file system in itself....

     is a compressed loopback device
    Loop device
    In Unix-like operating systems, a loop device, vnd , or lofi is a pseudo-device that makes a file accessible as a block device....

     module for the Linux kernel
    Linux kernel
    The Linux kernel is an operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software....

  • e2compr provides compression for ext2
    Ext2
    The ext2 or second extended filesystem is a file system for the Linux kernel. It was initially designed by Rémy Card as a replacement for the extended file system ....

  • List of file systems
  • Comparison of file systems
    Comparison of file systems
    -General information:-Limits:-Metadata:-Features:-Allocation and layout policies:-Supporting operating systems:-See also:* Comparison of archive formats* Comparison of file archivers* List of archive formats* List of file archivers...


Further reading


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK