This document estimates the RAM (memory) usage of Kubernetes components in a minimal High Availability (HA) setup. It includes the memory requirements for control plane nodes, worker nodes, and shared tools, and it calculates the total memory footprint for the entire cluster.
- kube-apiserver
- Memory usage: ~512 MB
- kube-controller-manager
- Memory usage: ~200 MB
- kube-scheduler
- Memory usage: ~100 MB
- etcd
- Memory usage: ~256 MB (varies with cluster size)
Total Control Plane Components RAM Usage: ~1,068 MB (~1.1 GB)
- kubelet
- Memory usage: ~512 MB
- kube-proxy
- Memory usage: ~64 MB
Total Worker Node Components RAM Usage: ~576 MB (~0.6 GB)
- Container Runtime (e.g., containerd or CRI-O)
- Memory usage: ~128 MB
- Networking Plugin (e.g., Calico, Flannel)
- Memory usage: ~64 MB
- Additional Tools (e.g., kubectl, Helm)
- Memory usage: ~32 MB
Total Shared Components RAM Usage per Node: ~224 MB (~0.2 GB)
-
Control Plane Node:
- Kubernetes components: ~1,068 MB
- Shared components: ~224 MB
- Total: ~1,292 MB (~1.3 GB)
-
Worker Node:
- Kubernetes components: ~576 MB
- Shared components: ~224 MB
- Total: ~800 MB (~0.8 GB)
- Control Plane Nodes (3 × 1,292 MB): 3,876 MB (~3.9 GB)
- Worker Nodes (2 × 800 MB): 1,600 MB (~1.6 GB)
Total RAM for HA Setup: ~5,476 MB (~5.5 GB)
- These estimates cover the memory usage of Kubernetes components only. Additional memory will be needed for application workloads, monitoring tools, and logging systems.
- Recommended memory for nodes is typically higher to provide headroom for operational stability:
- Control Plane Node: 2 GB
- Worker Node: 1 GB
- Real-world memory usage may vary depending on cluster size, workloads, and configuration settings.