Async - Minecraft Entity Multi-Threading Mod ⚙️

Async is a Fabric mod designed to improve entity performance by processing them in parallel using multiple CPU cores and threads.

Important❗

Async is currently in alpha testing and is experimental. Its use may lead to incorrect entity behavior and crashes.

What is Async? 🤔

Async is a Fabric mod that enhances the performance of entity processing. The mod leverages multithreading, which allows multiple CPU cores to improve performance when handling a large number of entities.

💡 Key Benefits:

• ⚡ Improved TPS: Maintains stable tick times even with a large number of entities.
• 🚀 Multithreading: Utilizes multiple CPU cores for parallel entity processing.

📊 Performance Comparison (9000 Villagers)

Configuration	TPS	MSPT
Lithium + Async	20	41.8
Lithium (without Async)	4.4	225.4
Purpur	5.72	176.18

🛠️ Test Configuration

• Processor: AMD Ryzen 9 7950X3D
• RAM: 64 GB (16 GB allocated to the server)
• Minecraft Version: 1.21.4
• Number of Entities: 9000
• Entity Type: Villagers

Mod List

Concurrent Chunk Management Engine, Fabric API, FerriteCore, Lithium, ScalableLux, ServerCore, StackDeobfuscator, TT20 (TPS Fixer), Tectonic, Very Many Players, Fabric Carpet.

🔧 Commands

• /async config toggle — Enables or disables the mod in-game (no server restart required). Use this command to instantly see how Async improves your server.
• /async config setEntityMoveSync — Disables parallel processing of entity movement. Useful for preventing potential desynchronization with vanilla logic (disabled by default). Always enabled for items.
• /async config setDisableTNT — Enables or disables parallel processing of TNT. (Disabled by default as the feature is unstable).
• /async stats — Displays the number of threads in use.
• /async stats entity — Shows the number of entities processed by Async in various worlds.

📥 Download

The mod is available on Modrinth

🔄 Minecraft Version Support

Full support is provided only for the latest version of Minecraft. Older versions receive critical fixes only. Support for older Minecraft snapshots is not planned.

📭 Feedback

Our tracker for feedback and bug reports is available on GitHub:

You can also chat with us on Discord:

🙌 Acknowledgements

This mod is based on code from MCMTFabric, which in turn was based on JMT-MCMT. Huge thanks to Grider and jediminer543 for their invaluable contributions!