The BCU Tool: Build & AI Optimization
As Sons of the Forest communities grow into 2026, many dedicated servers face "Entity Bloat." A server with 50,000+ placed logs and a hundred wandering mutants will experience massive TPS (Ticks Per Second) drops. The **Build Cleanup Utility (BCU)**, introduced in early 2026, is the official solution for maintaining high-performance community servers.
🛠️ BCU Core Functions
- Structure Compaction: Merges multiple log-entities into a single optimized "Wall" object, reducing the physics-engine load.
- Entity Tethering 2.0: Only calculates the AI for mutants within 200m of a player, putting distant mutants into "Deep Sleep" mode.
- Fragile Decay: Automatically removes abandoned structures that haven't been repaired for 14 real-world days.
Implementing AI Batching
A major cause of server stutter in the 2025/2026 meta is mutant AI calculation. Use the BCU to enable **Mutant AI Batching** via your DedicatedServer.cfg:
🧟 Batch Frequency
Set Mutant_AI_Batching=true. The server will update mutant positions every 2 ticks instead of every 1, doubling your AI CPU capacity with zero visible difference.
📍 Spawning Caps
The BCU allows you to set **Zone-Based Spawning**. Limit the number of mutants in the "Base Areas" to 20, while allowing 100+ in the "Wilderness" for a more balanced load.
Building Optimization (BCU Commands)
If you are an admin on a server with "Mega-Fortresses," run these commands once a week to maintain 60 FPS for your players:
# BCU Console Commands (2026)
/bcu compact_all # Merges log physics into single-body objects.
/bcu purge_abandoned # Deletes structures with zero player interaction in 14 days.
/bcu stat_report # Generates a report of the top 5 lag-causing builds.
Recommended BCU Configurations:
| Setting | Value | Impact |
|---|---|---|
| Structure_LOD_Distance | 150.0 | Dramatically improves player FPS in base areas. |
| AI_Sleep_Radius | 300.0 | Reduces CPU load by deactivating distant mutants. |
| Physics_Refresh_Rate | 30 | Lowering to 30Hz stabilizes "Falling Tree" desync. |
Does the BCU tool delete player builds?
Only if they are **unrepaired and abandoned**. The purge_abandoned command ignores any build within a 50m radius of a Powered Flame Altar or a recent player login point.
Can I use BCU on a local save?
The BCU is primarily a **Dedicated Server binary extension**. However, you can use the compact_all command on local saves if you have the 'Admin Console' mod enabled.
Is 'Building Decay' mandatory?
No. You can set Structure_Decay_Enabled=false in the BCU settings if you want to allow players to keep their ruins forever, though this will eventually degrade performance.
Next Steps
- Explore the Part 2 Bunker Cities
- Thermal Insulation & Base Design
- Back to Sons of the Forest Wiki Home
BCU-Managed Hosting: Supercraft’s SotF servers include **Auto-BCU** scripts. We automatically run compaction and stale-build purges in the background, ensuring your server stays as fast as the day you launched it.