Minecraft's Dumbest Server Performance Mod.
What Does This Do?
Does it Tick is an entity ticking optimization mod, that greatly speeds up server performance with a simple philosophy:
If a sheep is 12 chunks away, and no one sees it, does it tick?
The answer is no, it shouldn't, and neither should lots of things that don't affect the player experience. So we simply turn it off! This surprisingly causes little issues, besides breaking some expected behaviour of AFK farms.
However, this mod also integrates with both FTB Chunks and Open Parties and Claims, so you can simply claim chunks where you want entities to tick as normal when you are not near them.
Since this is a fairly invasive optimization mod, a long list of config options is provided so that you can disable the optimization for certain entities. A reasonably sane default whitelist is included so that entities like the Ender Dragon, Ghasts, and other things that need to tick for gameplay reasons will not be effected.
If you experience any issues with modded entities not working, or being frozen in place when far away, make a GitHub issue!