Karpenter

Overview

Karpenter provisions right-sized nodes directly from cloud-provider APIs based on aggregate pending-pod resource requests — no node groups, sub-minute scale-up, active consolidation to cheaper nodes. vs Cluster Autoscaler: no predefined ASGs, picks from all instance types, bin-packs, first-class spot (on-demand fallback is opt-in, NOT automatic).

Core dependency: accurate pod resources.requests — Karpenter bin-packs against requests (limits are ignored for scheduling). Instance-type flexibility is the engine of bin-packing and consolidation; over-constraining families defeats both and narrows the spot pool.

This skill targets the v1 API (Karpenter 1.0+): NodePool = karpenter.sh/v1, EC2NodeClass = karpenter.k8s.aws/v1. The pre-v1 Provisioner/AWSNodeTemplate and v1beta1 are gone (see Currency).

Examples

1. Basic NodePool (broad, flexible)