Containerization has become the standard for building and deploying cloud-native applications, providing portability and efficiency. CoreOS, a container-focused OS, is implementing a cloud native approach to customizing OS images. Using container images to distribute and update your operating system across your cluster. With CoreOS layering, you can pick an OS image, mutate it to your specific requirements, and then deploy it directly to nodes without creating local hysteresis. This led to the need for the OS (yes with the kernel!) to be packed inside a container image in such a manner that the subsequent updates to it only download the delta between the two. We will go behind the scenes, and explain how rpm-ostree achieved to solve the multi-objective bin packing problem using data science. We will explain the crucial design considerations that helped save more than 100MB in aggregate over Fedora CoreOS upgrades in a node. Join us to learn from our mistakes and make updates easier!
