Compression

mo: prerequisite software Data Compression as it relates to mediawiki.

what is compression
Data_compression

Compression of Databases
The WikiMedia Database is quite large, (it would take days to download at standard dial up modem speeds), so wikimedia compresses the database dumps. (bandwidth can cost about a dollar per gigabyte!) Bandwidth cost

Compression of articles
It is possible, with apache and mod_deflate, to compress individual pages served. Both the browser and the server must support it, and it is normally negotiated, (with uncompressed version available).

This, however, can put extra stress on certain parts of the server infrastructure.

bzip2 (bz2)
bzip2 is a freely available, patent free, high-quality data compressor. It typically compresses files to within 10% to 15% of the best available techniques, whilst being around twice as fast at compression and six times faster at decompression.

bzip2 compresses files using the Burrows-Wheeler block-sorting text compression algorithm, and Huffman coding. Compression is generally considerably better than that achieved by more conventional LZ77/LZ78-based compressors, and approaches the performance of the PPM family of statistical compressors.

You can get bzip2 for free at the fopllowing locations:
 * Microsoft Windows: a command-line Windows version of bzip2 is available for free under a BSD license (bzip2 ). A GUI file archiver, 7-zip, that is also able to open bz2 compressed files is available for free (7-zip, ).
 * GNU/Linux: most distributions ship with the command-line bzip2 tool. E.g. on Debian/GNU Linux it's apt-gettable by apt-get install bzip2.
 * MacOS X: ships with the command-line bzip2 tool.

request for deletion
--Elian 00:39, 23 Jul 2004 (UTC)
 * (see talk page for rational of this page)