No Random Ticks

Stop blocks and fluids from random ticks or ticks

Random ticks

Most blocks in the game perform randomTicks and this part is quiet optimized in itself. Yet, the more blocks you have the bigger the strain on a server. Even stairs do randomTick() for some mysterious reason.
Preventing randomTick() is a somewhat safe option. You just prevent some mechanics from running, like copper weathering, bamboo growing. At least in vanilla I haven't found any breaking blocks that crash the game if they are banned. I have randomly selected 50% of all the blocks in the game and banned them. No issues.

Here is some data from profiler:
Versions: Minecraft 1.20.1, Forge 4.30.0.
Mods: NoRandomTicks and WorldEdit
Blocks: 3800 bamboo, 5800 acacia stairs, 4200 birch leaves

How to understand this numbers

Vanilla:

[08] |   |   |   |   |   |   |   |   tickBlocks(40401/201) - 64.88%/5.94%
[09] |   |   |   |   |   |   |   |   |   randomTick(53667/267) - 72.67%/4.32%
[10] |   |   |   |   |   |   |   |   |   |   #getChunkCacheMiss 4309/21
[10] |   |   |   |   |   |   |   |   |   |   #getChunk 97830/486
[10] |   |   |   |   |   |   |   |   |   |   unspecified(53667/267) - 82.14%/3.55%
[10] |   |   |   |   |   |   |   |   |   |   queueCheckLight(4755/24) - 8.67%/0.37%
[10] |   |   |   |   |   |   |   |   |   |   updateSkyLightSources(4755/24) - 8.45%/0.37%
[10] |   |   |   |   |   |   |   |   |   |   no_random_tick_check_blocks(6428/32) - 0.74%/0.03%

Blacklisted:

[08] |   |   |   |   |   |   |   |   tickBlocks(40401/201) - 40.26%/1.50%
[09] |   |   |   |   |   |   |   |   |   unspecified(40401/201) - 75.91%/1.14%
[09] |   |   |   |   |   |   |   |   |   randomTick(53064/264) - 24.09%/0.36%
[10] |   |   |   |   |   |   |   |   |   |   #getChunkCacheMiss 43/0
[10] |   |   |   |   |   |   |   |   |   |   #getChunk 882/4
[10] |   |   |   |   |   |   |   |   |   |   unspecified(53064/264) - 92.69%/0.34%
[10] |   |   |   |   |   |   |   |   |   |   no_random_tick_check_blocks(5231/26) - 7.31%/0.03%

Consider +-1% as error

Ticks

This territory is full of surprizes. Some blocks may be unaffected at all while others may stop working or only half of the functionality may be gone. E.g. minecraft:fire, if you ban it from ticking the only thing that will happen is it won't destroy block (if set on wood for example) and extinguish. So, basically behaves like on netherrack.
Furnaces don't give a shit. So, unless you know how a block works or ready for a long process of trail & error, I recommend to avoid this feature.

Fluids

Since version 0.3 (1.21.1) or 0.4 (1.20.1), you are able to prevent fluids from ticking and random ticking. Be careful with that option. Fluids without ticks just stay like a liquid block forever, but they will interact with the world and neighbors. Vanilla has only two liquids, water and lava, so my tests are somewhat limited. Only lava has a random tick method, and all that it does is set things on fire. You can toggle that behavior in the gamerules, so random tick prevention may be useful only for liquids from other mods. Also remember that fluids have at least two types: flowing and normal.

Debug

Since version 0.3 (1.21.1) or 0.4 (1.20.1), I've added the option to display on load and reload of the config what was blocked and what failed.

Regex

Since version 0.4

@pigporker (curseforge) suggested to add a regex support, so here it is. Regex works together with per block arrays, on config load/reload they are combined in one blacklist. You can write huge-ass patterns or divide them into an array of smaller patterns, it's up to you. Regex is super useful but not very user-friendly, so errors aren't affected by DEBUG option of the config. They are always ON. I tried to make them useful and verbose to help you debug. For example a messed up pattern hints you to a problem:

[02:12:20] [modloading-worker-0/WARN] [NoRandomticksMod/]: Rejected invalid regex pattern '^[minecraft:.*': Unclosed character class near index 13
^[minecraft:.*
             ^

Usage

The way I see it, this mod may help you:

• Squeeze some performance if you are in a really tight spot. This is for a server, remember; this mod helps the server way more than the client.
• Prevent some mechanics from happening while leaving the block or fluid.
• Debugging

If you want to see a performance comparison, see readme.md on the mod's GitHub page.