ModsJava
Bye?Pregen!
Reduce MSPT spikes and server freezes caused by chunk generation and speed it up. Free Minecraft Java mod for 1.21.1, 1.20.1.
I don't know my version or loader
Open the Minecraft launcher and look at the profile you play on — it names both, like fabric-loader-1.21.4. The version also shows in the bottom-right corner of the game's main menu.
No loader in the profile name? Then it's plain Minecraft, and these mods won't run — you need Fabric or NeoForge installed first.
This mod optimizes world-generation block placement, post-processing, and the cascading chunk-loading requests that post-processing can trigger. Combined with reduced memory allocations, it significantly lowers the performance cost of terrain generation and exploration.
BACKUP YOUR SAVE DATA BEFROE USE
Features
- Lower MSPT during chunk generation
- Less server freezing during chunk generation
- Fewer cascading chunk-request
- Reduced memory allocation overhead
Compatibility:
Automatically disables C2ME's FluidPostProcessingFilter option
Test Environment
- Mods: C2ME + Lithium
- Render Distance: 43 chunks
- Memory: 12 GB RAM
Before:
After:
Results
- Average tick time reduced from 19 ms to 11 ms
- Maximum tick time reduced from 115 ms to 48 ms
- Significantly fewer MSPT spikes during terrain generation
Detailed Compare with Bye?Pregen 1.0.4
Verified by MCModsHub
- Ships as byepregen-1.0.1.jar — drop this file into the mods folder
- Download size: 18 KB
- Download link checked 23 Aug 2026 — working
These come from our own check of the pack file, not from the source page.