Spawn Chunks vs. Regular Chunks For Redstone Contraptions
This was the disagreement I was having while deciding where to put my iron farm. Ignoring that putting it in the spawn chunks would entail moving villagers 400 blocks, I wanted to see what the best choice was.
So a standard chunk is a 16 by 16 box of land that goes from the void under the bedrock to build height in all three dimensions. The spawn chunk is 9 chunks (16x16 blocks) in a 3x3 grid pattern where the spawn point is set. The spawn chunk also goes from the void to build height but it is only located in the Overworld. This is only for spawn chunks in 1.20.5 to 1.21.8. Discussed more in "Where are they going?" The spawn chunk is always loaded compared to regular chunks.
The follow up question I had was why are they different? Which compared to a lot of other questions this one is easy to answer! If 30 million blocks worth of chunks in all four cardinal directions were loaded at once, the game would be unplayable. I'm playing on a laptop, slightly better than some laptops, but that many chunks sounds like a lot of work. Therefore, regular chunks stop getting loaded.
So why are spawn chunks always loaded? Are they super necessary? Actually not anymore! They were originally a bug fix. If a player had an invalid bed and had to be sent to an unloaded spawn chunk it would cause a lag spike. The quick fix that Mojang did was to constantly load the chunks.
Spawn chunks are going away in 1.21.9 / Fall Drop 2025 (most recent update and currently playing on 1.21.8). So their days are numbered. They were already updated on 1.20.5 to make their chunk propagation default to 3x3 instead of 19x19. If you are also confused about that sentence, here's what it means. The spawn chunks were previously (between Beta 1.8 and 1.20.4) made of a 19x19 chunk area. The 16x16 area was actively loaded and the chunks surround it were "lazy chunks". Now, (1.20.5 to 1.21.8) the spawn chunks are a 3x3 chunk area. This is changeable through the spawn chunk radius command. It goes from 1 to 10 with the default being 2 and the 19x19 chunk area being 10.
From here on out, I'll be ignoring that the chunks are going away (therefore no reason to move villagers 400 blocks to a place I don't go often) for the purpose of learning. There is still much to learn about regular chunks! (or if you are me and spent several minutes with a confused look on your face scrolling reddit for answers :( )
What Will the Removal of Spawn Chunks Do?
Well, if you have a farm there, it will stop working. It will no longer be loaded and won't work without something loading it. Everyone should expect to have less lag as it is one less chunk being loaded. Also, there should be an increase to passive mob spawning as the passive mobs in the spawn chunks won't be affecting the mob cap. So very little, unless you have farms...
How Do Regular Chunks Work?
This definitely took a while. Minecraft Wiki throws a whole bunch of words like tickets, levels, and load types that are a little hard to decipher. So let's start as easy as I can.
If you've been in the Minecraft sphere, for any amount of time you have heard about chunk loading. Whether that be loading glitches or utilizing unloaded chunks or making a chunk loader. Loading is an important thing. In order for a chunk to load is has to be triggered. For the beginning of loading to be triggered the chunk receives a ticket.
There are three properties to a ticket: Level, Ticket Type, and an optional property of Time to live.
The level is typically between 22 and 44 in vanilla gameplay but can be different for modded gameplay. The level determines the load type, the lower the number the more features occurring on the chunk.
So for example the chunk you are standing in is between 31 and 22 and a chunk 30 million blocks away is in the 34 to 44 range.
Ticket type is what is sending the ticket, what's causing the chunk to be loaded. So this can be the player, a portal, the enderdragon, teleporting (such as going through the end portal or the teleport commands), forced ticket (created with the forcedload command), start (creates world spawn and spawn chunks),unknown (for quick information gathering for mob AI and spawning), and the light ticket (used in world gen.)
The most important for farms in vanilla with no commands (as far as I am aware) are the player and portal types.
This is why chunk loaders are minecarts going in and out of portals! A portal ticket is open for 300 ticks and has a level of 30 (Entity Ticking). This is stronger than the player but doesn't last as long. The portal ticket also only loads 9 chunks. The one the portal is in and the 8 around it.
This ticket is created by the player with a level of 31 (Entity Ticking). The amount of chunks rendered is determined by your render distance. If you've never touched your render distance and you are playing on 64-Bit Java, then your render distance is 12! This means there is a 25x25 chunk area that is at level 31, which is entity ticking. It is mapped out like this:
This shows how the chunks would be. The 25x25 chunk area of entity ticking would be surrounded by a 27x27 chunk area of block ticking chunks and so on. The amount of entity ticking chunks is determined by your render distance and the formula (l=2r+1). L being the chunk area and r being your render distance.
Mob generation is based off of blocks from player and not chunks. There is a 128 block circle where mobs can spawn around the player. So you would need to keep your mob farms closer to one centralized area if you wanted to AFK them at the same time, where other farms can be more spread out over the chunk area.
I've probably missed some things, purposefully ignored them, or didn't explain them well. If you have questions or corrections let me know so I can clarify. If you have a question it just creates more opportunity for me to learn so I always appreciate them!
No Minecraft day today :( I plan on having day 9 with day 10 as I didn't get much done. I hope this post was insightful! As always, anyone is welcome to ask questions or give tips in my asks, messages, reblogs, or comments. I would love to learn from you!
