Tuning the Engine: RAM & JVM Architecture
Project Zomboid operates within the Java Virtual Machine (JVM), a specialized software environment that manages memory and execution logic. Unlike C++ based game engines, Java using an automated Garbage Collection (GC) system to reclaim unused memory. If your server is incorrectly allocated or uses inefficient collection logic, players will experience debilitating “Micro-Stuttering,” synchronization delays, or catastrophic “Out of Memory” crashes. This guide ensures your memory pool is correctly calibrated for the intensive requirements of a persistent survival world.Difficulty
Intermediate
Time
6 Minutes
Technical Memory Allotment
Within the FREAKHOSTING Startup dashboard, you can define the boundaries of your Java memory heap.-Xmx(Maximum Heap): Defines the ceiling of memory the engine is authorized to consume.-Xms(Startup Heap): Specifies the volume of RAM the server reserves immediately during the boot sequence.- Strategic Recommendation: We strongly advise setting your Xms and Xmx to identical values. This eliminates the CPU overhead associated with the JVM constantly attempting to resize the memory heap during active gameplay.
Strategic Allocation Tiers
| Community Profile | Modload Intensity | Recommended RAM |
|---|---|---|
| Small Group (1-4 Players) | Pure Vanilla | 6 GB |
| Medium Squad (5-10 Players) | 20 - 50 Active Mods | 8 GB - 10 GB |
| Large Network (20+ Players) | Custom Maps + 100+ Mods | 12 GB - 16 GB+ |
Technical Hardening: Eliminating Stutters
If your server experiences periodic “freezes” (e.g., every 30 seconds), the Garbage Collector is likely initiating a “Stop-the-World” pause to purge large amounts of stale data.- The Solution: G1GC
- The Result
Adding the following flags to your startup instructs the JVM to use more modern, incremental collection logic:
-XX:+UseG1GC -XX:MaxGCPauseMillis=50Need Extra Help?
If you encounter any issues, our support team is ready to assist:- Live Chat: Quick assistance via our website.
- Support Ticket: Open a Ticket
- Discord: Join our Community
- Email: [email protected]
Last Updated: January 2026 | Project Zomboid: Memory optimized.