Knative 0.8: Smarter Traffic Management for Serverless

Introduction

Knative 0.8 landed on August 8, 2019, continuing the march toward stable serverless building blocks on Kubernetes. The release focuses on API stabilization, precise traffic-splitting, and elasticity improvements across Serving and Eventing components.

Serving Highlights

• v1alpha2 API: Updated Service, Route, and Configuration resources slim down status noise and clarify revision lifecycles.
• Traffic Policies: Weighted rollouts and blue/green routing default to percent-based splits with per-revision tagging.
• Autoscaling Signals: Concurrency and RPS-based scaling parameters tuned for bursty functions.

Eventing Progress

1. Sources Catalog: GitHub, GCP Pub/Sub, and Kafka sources mature with clearer CRDs.
2. Channel Consolidation: In-memory and Apache Kafka channels standardize status conditions and subscription management.
3. Broker/Trigger Alpha: Simplifies pub/sub fan-out using CloudEvents semantics.

Platform Integrations

• Tekton Pipelines: Trigger Knative deploys straight from PipelineRuns.
• Istio & Ambassador: Updated manifests support the latest ingress APIs.
• Cloud Provider Stacks: Anthos, OpenShift Serverless, and SAP Kyma bake 0.8 into managed offerings.

Getting Started

kubectl apply -f https://github.com/knative/serving/releases/download/v0.8.0/serving-crds.yaml
kubectl apply -f https://github.com/knative/serving/releases/download/v0.8.0/serving-core.yaml
kubectl apply -f https://github.com/knative/net-istio/releases/download/v0.8.0/release.yaml

Deploy a sample service and shift traffic gradually:

kn service update hello --image gcr.io/knative-samples/helloworld-go --tag current
kn service update hello --image gcr.io/knative-samples/helloworld-go:v2 --traffic current=80 --traffic @latest=20

Summary

Knative 0.8 demonstrates steady progress toward GA, giving platform teams confidence to run real applications atop Kubernetes-native serverless components.