14.6Resource Limits and Performance

Kubernetes resource requests and limits directly affect performance. Under-provisioned containers throttle at the worst possible moment:

# resource-config-for-performance.yaml
resources:
  requests:
    cpu: 500m        # guaranteed CPU allocation
    memory: 512Mi    # guaranteed memory allocation
  limits:
    cpu: 2000m       # burst capacity (4x request)
    memory: 1Gi      # hard memory limit (OOMKill if exceeded)

Performance Testing Resource Configurations

Test your service under different resource configurations to find the optimal settings:

Configuration	CPU Request/Limit	Memory Request/Limit	Test Result
Minimal	100m/500m	128Mi/256Mi	50 req/s, p99=2.5s, OOMKill under load
Conservative	250m/1000m	256Mi/512Mi	100 req/s, p99=800ms, stable
Optimal	500m/2000m	512Mi/1Gi	200 req/s, p99=400ms, stable
Generous	1000m/4000m	1Gi/2Gi	200 req/s, p99=350ms, diminishing returns

The "optimal" configuration achieves target performance without wasting resources. Load testing is the only way to find this sweet spot.