Deployment Without Resource Limits

Why Resource Limits Matter in Kubernetes

One of the most common Kubernetes misconfigurations is deploying containers without resource requests and limits. When you omit these fields, your containers can consume unlimited CPU and memory on the node, creating "noisy neighbor" problems that degrade other workloads.

Example Manifest with Missing Limits

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-app
  labels:
    app: web
spec:
  replicas: 3
  selector:
    matchLabels:
      app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
        - name: web
          image: nginx:1.25
          ports:
            - containerPort: 80

What the Validator Flags

• Warning: Container 'web' has no resource requests or limits defined
• Warning: No livenessProbe defined
• Info: No readinessProbe defined
• Warning: No securityContext.runAsNonRoot set

The Fix

Add resources to every container:

resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 256Mi

Impact of Missing Limits

Scenario	Without Limits	With Limits
Memory leak	OOMKills other pods	Only the leaking pod is killed
CPU spike	Starves neighboring pods	Throttled to its limit
Scheduling	No guaranteed resources	Scheduler places pod correctly
Cluster autoscaling	Cannot calculate needed capacity	Accurate scaling decisions

Setting appropriate requests and limits is essential for production workloads. Requests determine scheduling, while limits prevent resource exhaustion.