of Service for memory resources

Originally, Kubernetes used the v1 cgroups API. With that design, the QoS class for a pod only applied to CPU resources (such as `cpu_shares`). The Kubernetes cgroup manager uses `memory.limit_in_bytes` in v1 cgroups to limit the memory capacity for a container, and uses `oom_scores` to recommend an order for killing container processes if an out-of-memory event occurs. This implementation has shortcomings: for `Guaranteed` pods, memory can not be fully...