support elastic jobset

[kannon92]

Fixes #463

Add elastic jobset support (downscale/upscaling replicas of a Replicated Job).

Before this change, we treated ReplicateJobs (in JobSet.Spec) as immutable. This relaxes that restriction.

I choose to validate that names cannot be changed and the job templates must not change during updates. I don't see a reason for names to change and we also don't allow order change of the replicated job list so we can detect differences easily.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: kannon92
Once this PR has been reviewed and has the lgtm label, please assign ahg-g for approval. For more information see the Kubernetes Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[netlify]

✅ Deploy Preview for kubernetes-sigs-jobset canceled.

Name	Link
🔨 Latest commit	128d926
🔍 Latest deploy log	https://app.netlify.com/sites/kubernetes-sigs-jobset/deploys/662ac97030a00f0008db7248

[kannon92]

/assign @danielvegamyhre @ahg-g

[danielvegamyhre]

So the use case for this auto-provisioning adding new node pools, and relaxing this validation allows us to potentially autoscale the number of jobs in the replicatedJob to utilize the newly provisioned infrastructure?

[danielvegamyhre]

/lgtm

Will leave approval for @ahg-g

[danielvegamyhre]

/hold

[k8s-ci-robot]

PR needs rebase.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[kannon92]

@danielvegamyhre @googs1025 im on leave so im not going to be addressing these rebase for a little while. If you want this in, I would suggest maybe taking it up.

[k8s-ci-robot]

@kannon92: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-jobset-test-e2e-main-1-30	128d926	link	true	/test pull-jobset-test-e2e-main-1-30

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.