self-hosting/minecraft/papermc/Dockerfile

# Copyright (C) 2020 Jef Roosens

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.


FROM openjdk:8-slim

# Build arguments
ARG MC_VERSION
ARG PAPERMC_VERSION

# Create worlds and config directory
WORKDIR /app
RUN mkdir worlds config

# Download server file
ADD "https://papermc.io/api/v1/paper/$MC_VERSION/$PAPERMC_VERSION/download" server.jar

# Store the cache in an anonymous volume, which means it won't get stored in the other volumes
VOLUME /app/config/cache

WORKDIR /app/config

# Default value to keep users from eating up all ram accidentally
ENV XMS=4

# Document exposed ports
EXPOSE 25565

# We copy over the server jar(s) as well to make the backup more reproducible to deploy
ENTRYPOINT mv -n /app/*.jar /app/config && \
echo "eula=true" > /app/config/eula.txt && \
java \
-Xms"${XMS}G" \
-Xmx"${XMX:-$XMS}G" \
-XX:+UseG1GC \
-XX:+ParallelRefProcEnabled \
-XX:MaxGCPauseMillis=200 \
-XX:+UnlockExperimentalVMOptions \
-XX:+DisableExplicitGC \
-XX:+AlwaysPreTouch \
-XX:G1NewSizePercent="$([ $XMS -gt 12 ] && echo 40 || echo 30)" \
-XX:G1MaxNewSizePercent="$([ $XMS -gt 12 ] && echo 50 || echo 40)" \
-XX:G1HeapRegionSize="$([ $XMS -gt 12 ] && echo 16 || echo 8)"M \
-XX:G1ReservePercent="$([ $XMS -gt 12 ] && echo 15 || echo 20)" \
-XX:G1HeapWastePercent=5 \
-XX:G1MixedGCCountTarget=4 \
-XX:InitiatingHeapOccupancyPercent="$([ $XMS -gt 12 ] && echo 20 || echo 15)" \
-XX:G1MixedGCLiveThresholdPercent=90 \
-XX:G1RSetUpdatingPauseTimePercent=5 \
-XX:SurvivorRatio=32 \
-XX:+PerfDisableSharedMem \
-XX:MaxTenuringThreshold=1 \
-Dusing.aikars.flags=https://mcflags.emc.gs \
-Daikars.new.flags=true \
-jar /app/server.jar \
--universe /app/worlds \
--nogui