Docker alpine smaller image footprint

Wed, 20 Jul 2016 00:00:00 +0000

Working with docker images to minimise the footprint i.e the size if a image. There is a few things that you can do to get smaller images. I will show some examples for a small go and python3 service built in a Debian and alpine linux based image to compare the result and the footprint that a image.

The key to building small docker images is only use one RUN step in the Dockerfile. Why you might think. Every RUN in docker is a layer. The layer will contain what you do in that layer like adding package cache. If you then remove the cache in a later RUN you will still have it in the parent layers. So what you do is use al lot of && in the same RUN and in the end remove the files and cache you don’t need. Selecting the base image will affect you the most when it comes to footprint. I will look on Debian and alpine based images.

Alpine on qone.io

Docker alpine smaller image footprint