Karpenter

Karpenter is an open source tool that adds the right compute nodes to a Kubernetes cluster when workloads need them. It also removes nodes that are no longer needed, which helps keep cloud costs under control.

Karpenter watches for pods that cannot be scheduled because the cluster lacks capacity. It then launches nodes that fit the resource requests of those pods. It also looks for under-used nodes, replaces expensive ones with cheaper options and moves workloads onto fewer nodes where possible.

• Launch nodes when pods cannot be scheduled
• Remove and consolidate under-used nodes
• Pick cheaper compute options when they fit
• Sensible defaults set in one NodePool resource
• Works with any Kubernetes cluster and cloud

Platform and operations teams that run Kubernetes and want less manual work when scaling nodes. It suits teams whose traffic and workloads change often.

Karpenter is licensed under Apache 2.0, so the software is free to use. You still pay for the cloud compute the nodes use. The project started at AWS, and it runs inside your own cluster, so you install and manage it yourself.