Hello,
I was looking into google/cadvisor docker image that is only 47 megs large and wondering how we can improve. To some extend it is so small because of the Go lang, but not only.
Here are the results:
base image with JRE 8 and Alpine linux: 76.8 MB
wildfly 10.1.0.Final image 215 MB
hawkular-services 320 MB
Just for the record, here is status quo:
base CentOS image w/ JDK 8: 149 MB
wf image: 580 MB
hawkular-services image 672 MB
All the mini-images are based on Alpine (that itself is based on BusyBox), so the price for it is less convenience when debugging the images.
I also removed
9.2M /opt/jboss/wildfly/docs
and wanted to remove
9.0M /opt/jboss/wildfly/modules/system/layers/base/org/hibernate
5.1M /opt/jboss/wildfly/modules/system/layers/base/org/apache/lucene
5.6M /opt/jboss/wildfly/modules/system/layers/base/org/apache/cxf
but from some reason the h-services fails to start because it didn't found some class from that hibernate module, so I rather put it back.
What also helped was squashing all the image layers into 1. This makes the download faster and possibly the image smaller. When applying docker-squash [1] to the current h-services image it saves ~50megs
I am aware that this probably wont fly with some RH policy that we should base our SW on Fedora/RHEL base OS images, but I am gonna use them for development and because I often run out of space because of Docker.
Oh and I haven't published it on dockerhub yet, but the repo is here [2]
jk