JFFS2: Difference between revisions

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== Algoritms ==
== Algoritms ==

=== Zlib ===
=== Zlib ===
Lossless data-compression library,
Lossless data-compression library,
* [http://www.zlib.net/manual.html Manual]
* [http://www.zlib.net/manual.html Manual]
* [http://www.zlib.net/zlib_how.html Examples]
* [http://www.zlib.net/zlib_how.html Examples]

=== rubin ===
=== rubin ===
This simple algorithm is faster than zlib but not quite as effective.

=== rtime ===
=== rtime ===
This is a simple algorithm that often manages to squeeze extra few
bytes from data already compressed with gzip

== Links ==
== Links ==
*[http://en.wikipedia.org/wiki/JFFS2 JFFS2] at wikipedia
*[http://en.wikipedia.org/wiki/JFFS2 JFFS2] at wikipedia

Revision as of 05:08, 19 December 2006

I'd like to see some more info on JFFS2, the compression algorithm (or algorithms) that will be used, and ideally, some data on how well various files might be expected to compress with examples. Some photos, diagrams, xml, python code, etc.


JFFS2 Is the Journalling Flash File System version 2, jffs2 is a log-structured file system for flash memory devices and has support for NAND devices, also Hard links and compresion algoritms like zlib, rubin and rtime. Jffs2 also has a garbage collection algorithm that eliminates unnecessary I/O.

Algoritms

Zlib

Lossless data-compression library,

rubin

This simple algorithm is faster than zlib but not quite as effective.

rtime

This is a simple algorithm that often manages to squeeze extra few bytes from data already compressed with gzip

Links