Mesos + Kubernetes is one alternative to achieve Pod orchestration (Kubernetes) and resource allocation (Mesos). But how does Google Container Engine carry out resource/task sharing for Kubernetes? To my understanding, Kubernetes does not itself offer this.
Kubernetes actually does do this. The master schedules each pod onto a worker node, and each node communicates with the master to receive the work it should do. The scheduler does bin packing based on resource requests.
We're working on improving the scheduler to use resource usage as well (what a process is actually using, rather than what a process requested)
The kubelet daemon on the worker then communicates with Docker to actually run the container.
Hope that helps!