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Set min-node-count appropriately - AWS Prescriptive Guidance
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Set min-node-count appropriately

The minimum node count per node group determines your cost floor — set it too high and you pay for idle nodes 24/7, set it too low and you risk cold-start delays during traffic spikes.

Assessment criteria for min-node-count:

  • Calculate total resource requests for always-on workloads (monitoring, logging, mesh)

  • Add headroom for DaemonSets (each node runs kube-proxy, VPC CNI, monitoring agent)

  • Factor in PDB requirements — if a deployment requires 2 replicas across 2 AZs, minimum is 2 nodes

min_nodes = ceil(total_pod_requests_at_lowest_traffic / allocatable_per_node)

For the commands to assess your current min-node-count, check off-peak utilization, and calculate the optimal minimum based on DaemonSet overhead and PDB requirements verify-min-node-count.sh .

Actions

Audit your node group minimums against actual off-peak utilization. If nodes at minimum count run below 40% CPU/memory, reduce the minimum. For non-production clusters, set minSize=0 with Karpenter or minSize=1 with Cluster Autoscaler to allow full scale-down outside business hours.

# Update min size for a managed node group
aws eks update-nodegroup-config --cluster-name my-cluster \
  --nodegroup-name my-nodegroup \
  --scaling-config minSize=2,maxSize=20,desiredSize=3

Key takeaway: Every node in your minimum count runs 24/7/365 regardless of demand. An over-provisioned minimum of just 2 extra nodes costs you the equivalent of those instances running all year — often thousands of dollars per node group.