#QoS

K8s Intermediate #4: resources.requests / limits — Pod Resource Requests and Limits

[#3](/en/posts/k8s-intermediate-3) covered the path of external traffic into the cluster. This post moves the viewpoint back inside the Pod — the model of how a container requests and is limited on CPU and memory. `resources.requests` is what the scheduler sees when picking a node; `resources.limits` is the runtime cap kubelet enforces. This post walks through the separation of the two, QoS classes (Guaranteed / Burstable / BestEffort), the difference between CPU throttling and OOMKilled, JVM/Go runtime cgroup awareness, and the pattern of setting namespace defaults via `LimitRange` — all in one cycle.