Wale: A Dockerfile-Based Approach to Deduplicate Shared Libraries in Docker Containers
Corrado Santoro, Fabrizio Messina, Fabio D’Urso, Federico Fausto Santoro · 2018
This paper presents a simple, novel approach to deduplicate disk space needed by shared application libraries in Docker containers. The described approach relies on the deployment of a single Docker image called "core-image", designed to collect all the libraries shared among the various Docker images. The management of the Docker images is made by means of the automatic manipulation of the related Dockerfile, i.e. the text files which describe the composition of Docker images. The user is asked to enrich its own Dockerfiles with a number of directives, as Dockerfile comments, that represent the meta-data needed to identify the common libraries among Docker images. In this way, common libraries and files are moved into the core-image, which is rebuilt again along with the new image containers. The latter will contain only libraries and files that are not shared. The paper includes the description of a simple but realistic case study which proves the effectiveness of the approach in terms of saved disk space.