Wurm Unlimited Server Performance and Java Memory
Wurm worlds accumulate history. Map size, terrain, creatures, items, deeds and database age usually matter more than a single evening’s player count.
Plan by world
| World | Starting RAM | Workload |
|---|---|---|
| Small private map | 4 GB | Small group and modest database. |
| Medium community map | 6 GB | Long-lived settlements and mods. |
| Large or public world | 12 GB+ | Many entities, players and scheduled tasks. |
Diagnose lag before tuning
- Measure heap and system memory while the lag occurs.
- Compare a quiet restart with a full community session.
- Check whether a mod, creature load or database task began recently.
- Keep enough headroom for saves and backups.
- Test Java changes on a copy before a public restart.
More heap cannot repair an exposed RMI port, a broken mod or a world that was never saved cleanly. Identify the bottleneck first.
See the backup guide and Wurm Unlimited hosting.