Start script generator
What flags do I choose?
The default is the FeatherMC performance preset, the same flags as FeatherMC’s own start.sh and start.bat.
It uses ZGC, which collects garbage concurrently, so pauses stay well under a millisecond and the server does not
freeze to reclaim memory. -XX:-ZUncommit keeps spare RAM instead of handing it back to the OS, and the script sets
the minimum and maximum heap to the same size, so the heap never resizes while the server runs. Giving ZGC generous
RAM is the point: it uses the headroom to avoid pauses.
If you want the community standard instead, pick Conservative, which is the same tuned G1 setup as GC_MODE=conservative (Aikar’s flags).
Choose None to use the JVM defaults.
Leave about 1 GB of your server’s RAM for the JVM itself. For example, use 4GB in a 5GB container.
Flags are a trade-off, so check the result with /spark tps and /spark gc.
The generator gives you the start command. On a panel such as Pterodactyl, paste it into the startup command field. To run
FeatherMC yourself, tick Create a start script to get a ready-made start.sh or start.bat.
Memory: 4GB
4GB8GB12GB16GB20GB Custom
File name:
Flags:
Adapted from the PaperMC docs (CC BY-SA 4.0). About these docs.