HorizontalPodAutoscaler v2beta1 is deprecated in v1.22+

[Ijmcclung]

Expected Behavior

A released deployment manifest that does not use the deprecated HorizontalPodAutoscaler.

Actual Behavior

tekton-pipelines uses HorizontalPodAutoscaler in the deployment manifest

Steps to Reproduce the Problem

1. Download latest release yaml or v0.27.3 yaml

Additional Info

• Kubernetes version: 1.23

• tkn version : Pipeline version: v0.27.3 Triggers version: v0.16.0 Dashboard version: v0.20.0

• Full warning: autoscaling/v2beta1 HorizontalPodAutoscaler is deprecated in v1.22+, unavailable in v1.2 5+; use autoscaling/v2 HorizontalPodAutoscaler

[vdemeester]

From #5130

Alright, this fails because apiVersion: autoscaling/v2, kind: HorizontalPodAutoscaler is available starting with 1.23. So v2beta1 is, weirdly enough, deprecated in 1.22+ but the v2 is only available in 1.23.

Bumping to autoscaling/v2 would effectively mean we require a minimum version of kubernetes to be 1.23. We, most likely, will have to do this before or at the same time as kubernetes 1.25 goes out or is "widely" available.

See https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale-walkthrough/ and https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/

[abayer]

/priority important-soon

Since we haven't even yet moved to k8s 1.22 minimum, I don't think we can bump straight to 1.23 in v0.39. Maybe v0.40?

[pritidesai]

Can we start testing on 1.23 and record any outstanding items?

[pritidesai]

/cc @pritidesai

[abayer]

Related knative/serving issue - https://github.com/knative/serving/issues/12806. Looks like Knative will be moving to k8s 1.23 as minimum version in October: https://github.com/knative/community/blob/main/mechanics/RELEASE-SCHEDULE.md. Whether that's a blocker for us moving to requiring 1.23, I don't know.

[pritidesai]

We can test but I am thinking it could be a blocker

[pritidesai]

@dprotaso mentioned 1.23 is not in GKE regular channel - https://github.com/knative/community/pull/1140 😞

[pritidesai]

Since we haven't even yet moved to k8s 1.22 minimum, I don't think we can bump straight to 1.23 in v0.39. Maybe v0.40?

I thought the minimum was already 1.22 but that's not the case as per our documentation. But the default minimum version needed for knative is 1.22 as per https://github.com/tektoncd/pipeline/blob/main/vendor/knative.dev/pkg/version/version.go#L36 And the PR - https://github.com/tektoncd/pipeline/pull/4928.

I missed this action-required in the release notes 😞