Can you explain the concepts of limits and resource requests in Kubernetes?

In Kubernetes, resource limits and requests are used to manage CPU and memory consumption by containers:

• Requests: This is the minimum amount of resources that a container is guaranteed to receive. The Kubernetes scheduler uses requests to determine on which node to place the pod, based on available resources.

• Limits: This is the maximum amount of resources that a container can use. If a container exceeds its CPU limit, its usage will be restricted; if it exceeds memory limits, the container may be killed.

Example of configuration in a Pod manifest:

resources:
  requests:
    memory: "128Mi"
    cpu: "250m"
  limits:
    memory: "256Mi"
    cpu: "500m"

Thus, requests help in efficient placement planning, and limits prevent a container from consuming excessive resources, which enhances cluster stability.