alpine-openjdk-11

This is image that installed binary file of openjdk 11 on alpine linux.

The image using this docker file is public to https://hub.docker.com/r/hirokimatsumoto/alpine-openjdk-11

Please refer to the following for the background that I needed. https://qiita.com/h-r-k-matsumoto/items/1725fc587ce127671560

important

There are people who still use this docker image.
I recommend using image of alpine tag of AdoptOpenJDK.
It is not musl base, but it is lightweight.

Thank you for reading.

Result

The size of 1 GB has been reduced to about 85 MB. Image size is the result output by the docker images command.

image type	jlink	size
openjdk:11-jdk	not used	1GB
openjdk:11-jdk	used	468MB
hirokimatsumoto/alpine-openjdk-11	not used	336MB
hirokimatsumoto/alpine-openjdk-11	used	84.6MB

Background problem

The docker image of openjdk 11 is published in the official respoitory of docker hub. https://hub.docker.com/_/openjdk/

This image has the following problem.

• openjdk:11-jdk tag image size is large. There is about 1 GB.
• Even if you use jlink, image size is 400 MB.
• Java Flight Recorder does not work in jre tag images.

The file size was confirmed with the following command.

$ sudo docker images |grep jdk
docker.io/openjdk                            11-jdk   f684efd78557  2 weeks ago         979 MB
$

I confirmed that libjvm.so becomes larger when using jlink.

$ docker run -it --rm openjdk:11-jdk /bin/sh
# ls -l /usr/lib/jvm/java-11-openjdk-amd64/lib/server/
total 34944
-rw-r--r-- 1 root root     1322 Jul 27 03:41 Xusage.txt
-r--r--r-- 1 root root 18210816 Jul 27 22:22 classes.jsa
-rw-r--r-- 1 root root    14440 Jul 27 03:41 libjsig.so
-rw-r--r-- 1 root root 17551048 Jul 27 03:41 libjvm.so
# jlink \
     --module-path /opt/java/jmods \
     --compress=2 \
     --add-modules java.base,java.logging,jdk.jfr  \
     --no-header-files \
     --no-man-pages \
     --output /opt/jdk-11-mini-runtime
#  ls -l /opt/jdk-11-mini-runtime/lib/server/
total 414452
-rw-r--r-- 1 root root      1322 Aug 14 09:41 Xusage.txt
-rw-r--r-- 1 root root     25384 Aug 14 09:41 libjsig.so
-rw-r--r-- 1 root root 424362808 Aug 14 09:41 libjvm.so
#

The generated libjvm.so increased to 424 MB. This problem is probably part of the following issue issue. docker-library/openjdk#217