Layers on EKS
Four tools appear in this walkthrough. They stack — they do not replace each other.
At a glance
Section titled “At a glance”| Layer | Question it answers | Runs where |
|---|---|---|
| Auto Mode | Which nodes exist? | AWS-managed compute for the data plane |
| Argo CD capability | Does the cluster match Git? | AWS control plane (not on your worker nodes) |
| Kueue | Which batch jobs may start now? | Pods in kueue-system on the cluster |
| KEDA | How many replicas from queue depth? | Pods in keda namespace on the cluster |
Scheduler versus provisioner
Section titled “Scheduler versus provisioner”This mirrors the EKS control plane parameters idea:
- Kueue decides whether a batch job may create pods (admission
Kueue admission gate — the decision whether a Job may create pods now, distinct from Kubernetes scheduling onto nodes.). - Auto Mode decides whether nodes should exist for schedulable pods (provision).
A job can be admitted by Kueue while pods stay Pending until Auto Mode adds a node — especially on Spot
Amazon EC2 Spot capacity — lower-cost interruptible compute; this lab uses a Spot ResourceFlavor separate from On-Demand..
Same GitOps pattern as KEDA
Section titled “Same GitOps pattern as KEDA”Neither Kueue
Kubernetes-native job admission controller — decides when batch Jobs may create pods based on quota, priority, and resource flavors. nor KEDA
Kubernetes Event-driven Autoscaling — scales Deployment or StatefulSet replicas from external metrics such as SQS queue depth. Complements Kueue; does not replace batch admission. is an EKS console add-on. Both deploy as Argo CD
Argo CD — GitOps controller that syncs cluster state from Git. This walkthrough uses the optional EKS managed Argo CD capability.Application
Argo CD Application — GitOps resource pointing at a Helm chart or manifest path to sync into the cluster. resources pointing at Helm
Package manager for Kubernetes — the Kueue controller installs from the upstream Helm chart via an Argo CD Application. charts or manifest paths in Git.
Batch versus serving
Section titled “Batch versus serving”| Workload | Tool |
|---|---|
| Job, CronJob, training batch | Kueue (this walkthrough) |
| Deployment scaled by SQS or CPU | KEDA or HPA |
| GitOps delivery of all of the above | Argo CD |
Illustrated comparison (and how they chain): KEDA vs Kueue.