Squashfs (.sfs) is a free (GPL) compressed read-only file system for the Linux kernel. Squashfs compresses files, inodes and directories, and supports block sizes up to 1024 KB for greater compression. Squashfs is intended for general read-only file system use, for archival use (i.e. in cases where a tar file may be used), and in constrained block device/memory systems (e.g. embedded systems) where low overhead is needed. The standard version of Squashfs uses gzip compression.
Uses
SquashFS is used by the LiveCD versions of Finnix, Ubuntu, DD-WRT and probably many more Linux distributions. The Helix forensics LiveCD also makes use of SquashFS. It is also combined with an UnionFS such as aufs to provide a read-write environment for live linux distributions. This takes advantage of both the SquashFS's high speed compression abilities with the ability to drastically alter the distribution while running it off of a cd. One distribution that uses this combo is Slax and its derivatives such as the Backtrack LiveCD as well as Debian Live.
See also
| Free software Portal |
- List of file systems
- Comparison of file systems
- Cramfs is another read-only compressed file system
- zisofs is a transparent compression extension to the ISO 9660 file system
- Cloop is a compressed loopback device module for the Linux kernel
- e2compr is an extension to the ext2 file system driver in the Linux kernel to support online compression
- http://www.squashfs-lzma.org/ has the patches for LZMA to achieve higher compression Vs Zlib
