Pregenerate your world with Chunky
New chunks are the most expensive thing a Minecraft server does, and they are generated exactly when a player walks into them. Pregenerating the area your players will use turns that into a one-time job while nobody is on.
Install Chunky
Resources, Plugins (Paper) or Mods (Fabric, Forge, NeoForge), search Chunky, Install, restart. Many modpacks ship it already; chunky in the console tells you.
Run it
In the Console:
chunky radius 3000
chunky startThat generates a 6,000 by 6,000 block square around spawn. chunky pause and chunky continue stop and resume; chunky progress shows where it is. For the nether and end:
chunky world world_nether
chunky radius 1000
chunky start(On vanilla, Fabric, Forge and NeoForge the nether is DIM-1 inside the world.)
How big and how long
| Radius | Blocks across | Time on a fast core (vanilla) |
|---|---|---|
| 2000 | 4,000 | about 30 minutes |
| 3000 | 6,000 | about an hour |
| 5000 | 10,000 | a few hours |
Modpacks with heavy worldgen take several times longer. Run it before launch night, keep the server up while it runs, and pair it with a world border of the same radius so nobody walks past the edge.
Disk
Pregenerated chunks take space: a 6,000 block square is a few GB on vanilla, more with modded worldgen. 30 GB is included; extra storage is a dollar per 10 GB. See Allocate RAM for the rest of the sizing.