AXFS

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AXFS (Advanced XIP Filesystem) is a compressed read-only file system for Linux, initially developed at Intel, and now maintained at Numonyx. It was designed to use execute in place (XIP) alongside compression aiming to reduce boot and program load times, while retaining a small memory footprint for embedded devices. This is achieved by mixing compressed and uncompressed pages in the same executable file. [1] AXFS is free software licensed under the GPL.

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Cramfs 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. [2]

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References

  1. Jonathan Corbet, (August 26, 2008) AXFS: a compressed, execute-in-place filesystem , lwn.net
  2. Justin Treon, (2008-05-09) "Demystifying embedded code storage". Archived from the original on 2012-09-03., LinuxDevices.com, "There are two XIP-enabled Linux filing systems that can be used for a Balanced XIP implementation: Linear XIP CRAMFS and AXFS. The Linear XIP CRAMFS decompresses files on a file-by-file basis, whereas AXFS decompresses files on a page-by-page basis offering more optimal Flash usage."

Further reading