CPU and memory resource limits defined for all pods

Containers without resource limits can consume unbounded CPU and memory — a runaway process, a traffic spike, or a memory leak starves other pods on the same node, triggering cascading OOM kills and node instability (CIS Kubernetes 5.7.4, ISO 25010 performance efficiency). Without resource requests, the Kubernetes scheduler has no data for placement decisions, leading to uneven node utilization and unexpected evictions under load. A single container with no memory limit can consume all memory on a node and bring down unrelated production workloads.

Define both requests and limits for CPU and memory on every container in k8s/deployment.yaml. Size requests based on typical load and limits based on the worst-case load the application can handle before it's better to restart than to degrade:

containers:
  - name: api
    resources:
      requests:
        cpu: 100m
        memory: 128Mi
      limits:
        cpu: 500m
        memory: 512Mi

For initial sizing, deploy without limits in a staging environment and observe actual usage with kubectl top pods. Set limits at 2x the 95th-percentile observed usage. Use LimitRange objects to enforce defaults at the namespace level so new containers cannot be deployed without resource constraints.