How to Reduce Server Lag Caused by Leftover Chunks

Understanding Where the Lag Comes From

Chunks kept loaded by players who have logged off still tick. Redstone, mobs, and machines in those chunks consume CPU and memory even though nobody is there to see them. Over a long session, dozens of abandoned loaded chunks can add up and drag down tick rate for everyone online.

Tightening the Timeout

Open the mod's config file in your server's config folder. Lower the timeout so chunks unload sooner after the last player leaves. Shorter timeouts free resources faster, but they also cut short any machine that needs to keep running. Pick a value that matches how your players actually use the server — if nobody runs overnight processing, a short timeout is safe.

Letting the Mod Clean Up Other Loaders

Make sure the cleanup of chunks loaded by other mods is enabled. This catches chunkloaders that players forgot about or that were left running by mods. If a specific mod needs to keep its chunks, add it to the exclusion list instead of disabling cleanup entirely.

Monitoring the Effect

After restarting, watch your server's tick time and memory during peak hours. You should see steadier performance as abandoned chunks are released. If lag persists, the cause may be elsewhere — check entity counts and redstone activity in currently loaded areas.