Paper Setup Guide

Paper is the most popular high-performance Minecraft server software. It is compatible with Spigot and Bukkit plugins and includes significant performance improvements over vanilla.

Prerequisites

An active AtomicHost Java server
Access to the control panel
Basic familiarity with Minecraft server files

Installation

AtomicHost pre-installs Paper for you. If you need to change the version:

Go to Startup in the panel
Under Variables, set Minecraft Version to the version you want (e.g. 1.21.1) — or leave it as latest to always track the newest release
Set Build Number if you need a specific Paper build, otherwise leave it as latest
Click Reinstall Server under Settings — this downloads the correct jar automatically

The Startup Command box above Variables is a read-only preview of the actual launch command — you won’t edit it directly, only the Variables that feed into it. There’s also a Docker Image dropdown for picking the Java runtime version itself, separate from the Minecraft/Paper version.

Danger

Reinstalling will stop your server and may delete or modify files during the process — back up first (see Backups).

Recommended server.properties

properties

# Performance
view-distance=8
simulation-distance=6
max-tick-time=60000

# Gameplay
difficulty=normal
gamemode=survival
pvp=true
spawn-protection=16

# Network
online-mode=true
max-players=20

Paper-specific Config (paper-world-defaults.yml)

yaml

chunks:
  auto-save-interval: 6000   # every 5 minutes
  delay-chunk-unloads-by: 10s

entities:
  spawning:
    per-player-mob-spawns: true
    counts:
      monsters: 70
      animals: 10

RAM Is Automatic, Not a Flag You Set

Some Paper guides tell you to hand-tune -Xms/-Xmx in the startup flags. On AtomicHost you don’t — since the Startup Command box is a read-only preview (see above), there’s nothing there to edit. The actual command uses -XX:MaxRAMPercentage=95.0 instead of a fixed -Xmx, which sizes the heap as a percentage of whatever your plan allocates rather than a number you maintain by hand. Upgrading your plan’s RAM raises the ceiling automatically — no startup flag to update to match.

Note

If you’re used to the Aikar flags (-XX:+UseG1GC, -XX:MaxGCPauseMillis=200, and friends) from other hosts, they’re a G1GC-tuning set layered on top of a fixed heap size, and aren’t something you can add here since the startup command isn’t user-editable. MaxRAMPercentage targets the same goal — good GC behavior without manual tuning — a different way.