Speeding Up World Pre-Generation with ScalableLux

Light updates are one of the hidden bottlenecks in chunk pre-generation: every new chunk needs its sky and block light computed before it can be saved. ScalableLux attacks exactly that cost, which makes it a strong companion to any pre-gen tool.

Set up for maximum throughput

Enable parallel light updates in the ScalableLux config and restart. Then run your pre-generator as usual. The mod does not change how chunks are generated — it only makes the lighting step faster — so no special flags are needed on the pre-gen side. Give the process enough heap memory, since faster lighting means chunks pile up in memory more quickly.

Tuning the load

If your machine has few cores, parallel updates can actually slow things down by causing contention. Watch CPU usage during pre-gen: if all cores are pegged and the chunk rate is not improving, turn parallelism off and rely on the base Starlight-derived speedups instead. On servers, avoid running pre-gen while players are online with parallel updates on, as the thread pool competes with normal tick work. Pre-generate during maintenance windows, then restart with the setting you want for live play.