Configuration
Java & memory settings
Heap size, GC flags, and what actually matters.
Kyrbit pre-configures sensible Java flags for vanilla Minecraft. You only need to touch this if you're running heavy mods.
Heap size
Your workload has a fixed RAM allocation tied to your size:
- Small: 2 GB
- Medium: 4 GB
- Large: 6 GB
- XL: 8 GB
- 2XL: 12 GB
Minecraft's generated startup command currently gives the game heap about 1 GB per credit and leaves the rest for the JVM, native allocations, disk cache, and the OS. That means Small starts with roughly 1 GB heap, Medium with 2 GB, Large with 3 GB, XL with 4 GB, and 2XL with 6 GB.
GC flags
We default to G1GC with Aikar's flags, which is the community standard for Minecraft servers. Don't change them unless you have a specific reason and a benchmark.
When to ask for more RAM
You need more RAM if:
- Your console shows repeated OutOfMemoryError.
- You've installed a heavy modpack (200+ mods) and TPS is fine but the server crashes after a few hours.
The fix is almost never "more RAM than your size includes" — it's usually "fewer mods" or "size up to the next tier".
Didn't find what you needed? Open a support ticket. During the closed beta you'll get a real human reply, usually within a few hours.