Container is the only first-class citizen in Docker
In 2013, the docker technology emerged, and container technology entered an era of rapid development. Containers utilize the Linux system isolation model, which includes namespace and cgroup. Container is the only first-class citizen in Docker.
Later, the kubernetes project became mainstream at the container orchestration level. So the “pause” container was introduced to accommodate the first-class citizen “Pod” in Kubernetes.
But the “pause” container is actually very confusing. Because a pod is not just a “pause” container that only provides a shared network namespace. Rather, it is a logical and physical collection of multiple containers.
Moreover, there are many unnecessary and complex logic judgments in the container runtime to differentiate the user’s container from the “pause” container, which also increases the difficulty of development virtually.