Savegame format

From OpenTTD
Jump to: navigation, search

<<Back to the Openttd.cfg (OpenTTD configuration file)

savegame_format is a variable of Openttd.cfg file:

The save game format to use. This is a client-setting only. This should only be used for testing only, as the best option for your system will be selected by default.

Valid options: [ <empty> | lzma | lzma:0 .. lzma:9 | zlib | zlib:0 .. zlib:9 | lzo | none ]

Default: <empty>

Some options may not be available if the required libraries have not been compiled in. Some options allow you to additionally specify a compression level.

Explanation of values: (from best to worst)

  • <empty> - Will use the best setting for your system
  • lzma - Use lzma2/xz compression.
    • lzma:0 .. lzma:9 (default: 2)
    • Level 2 compression is speed wise as fast as zlib level 6 compression (old default), but results in ~10% smaller saves. Higher compression levels are possible, and might improve savegame size by up to 25%, but are also up to 10 times slower. The next significant reduction in file size is at level 4, but that is already 4 times slower. Level 3 is primarily 50% slower while not improving the filesize, while level 0 and 1 are faster, but don't reduce savegame size much.
  • zlib - Use zlib compression.
    • zlib:0 .. zlib:9 (default: 6)
    • After level 6 the speed reduction is significant (1.5x to 2.5x slower per level), but the reduction in filesize is fairly insignificant (~1% for each step). Lower levels become ~5-10% bigger by each level than level 6 while level 1 is "only" 3 times as fast. Level 0 results in uncompressed savegames at about 8 times the cost of "none".
  • lzo - Use lzo compression.
    • Roughly 75% larger than zlib level 6 at only ~7% of the CPU usage.
  • none - Use no compression.
    • Roughly 5 times larger at only 1% of the CPU usage over zlib level 6.

The loading of save games is unaffected by the choice you have here.

Personal tools