Karpenter 0.1: High-Performance Kubernetes Node Autoscaler

Introduction

Karpenter 0.1 — High-Performance Kubernetes Node Autoscaler — was released on November 30, 2021.

This is a practical update aimed at making day‑to‑day Kubernetes work a bit more predictable.

In this release: AWS launches Karpenter 0.1, an open-source high-performance node autoscaler for Kubernetes clusters, providing faster node provisioning and better cost optimization.

High-Performance Node Provisioning

• Fast provisioning reduces node launch time through intelligent node selection and direct API calls.
• Bin packing optimizes pod placement to minimize the number of nodes required.
• Consolidation automatically removes underutilized nodes to reduce costs.
• Multiple instance types automatically selects the best instance type for each workload.

Cost Optimization

1. Spot instance integration enables automatic use of spot instances with intelligent fallback to on-demand.
2. Right-sizing selects the most cost-effective instance type for each pod’s resource requirements.
3. Consolidation reduces cluster costs by consolidating pods onto fewer nodes.
4. Interruption handling provides graceful handling of spot instance interruptions.

Kubernetes Integration

• Native Kubernetes integration uses standard Kubernetes APIs and resources.
• Pod requirements matching automatically matches pod requirements to appropriate instance types.
• Node affinity support respects pod affinity and anti-affinity rules.
• Taint and toleration support ensures nodes match pod scheduling constraints.

Getting Started

helm repo add karpenter https://charts.karpenter.sh
helm install karpenter karpenter/karpenter \
  --namespace karpenter \
  --create-namespace \
  --version 0.1.0

Create a Provisioner:

apiVersion: karpenter.sh/v1alpha5
kind: Provisioner
metadata:
  name: default
spec:
  requirements:
  - key: karpenter.k8s.aws/instance-category
    operator: In
    values: ["c", "m", "r"]
  - key: karpenter.k8s.aws/instance-generation
    operator: Gt
    values: ["2"]
  - key: kubernetes.io/arch
    operator: In
    values: ["amd64"]
  - key: karpenter.sh/capacity-type
    operator: In
    values: ["spot", "on-demand"]
  limits:
    resources:
      cpu: "1000"
  provider:
    subnetSelector:
      karpenter.sh/discovery: my-cluster
    securityGroupSelector:
      karpenter.sh/discovery: my-cluster
  ttlSecondsAfterEmpty: 30

Summary

Karpenter 0.1 introduces a new approach to Kubernetes node autoscaling, providing faster provisioning and better cost optimization than traditional autoscalers.