One Namespace Ate 80% of Cluster Memory: 4 Production-Grade Decisions for K8s ResourceQuota Multi-Tenant Governance
Overview The night before a major promotional event, all Pods in the test environment were stuck in Pending. kubectl top nodes showed node CPU usage at 35% and memory under 50%. The Deployment YAML had reasonable requests and limits. The problem? Not a resource shortage — the “ledger” was maxed out. A namespace’s ResourceQuota had hit its ceiling, and the admission controller was rejecting all new Pod creation requests. This incident forced me to re-examine the entire chain of K8s namespace-level resource governance....