Support Cluster-Autoscaler's ProvisioningRequest via two-stage admission

[trasc]

What would you like to be added:

Use two-stage admission to support Cluster-Autoscaler's ProvisioningRequest

Why is this needed:

The ProvisioningRequest API allows to request new nodes without creating Pods. Kueue can use it to provide high guarantees that the admitted workloads will fit in the cluster.

Completion requirements:

This enhancement requires the following artifacts:

• Design doc
• API change
• Docs update

The artifacts should be linked in subsequent comments.

[trasc]

/assign

[tenzen-y]

@trasc Could you update the issue description? I don't have any context as to why this feature is necessary.

[alculquicondor]

Sorry about that @tenzen-y. Updated the description.

There is a KEP coming. We are thinking of using the cmd/experimental folder to avoid tying this to the release of 0.5

[alculquicondor]

/assign @mwielgus
for design

[tenzen-y]

Sorry about that @tenzen-y. Updated the description.

@alculquicondor Alright. Thank you for the updates :)

There is a KEP coming. We are thinking of using the cmd/experimental folder to avoid tying this to the release of 0.5

It makes sense. IIUC, ProvisioningRequest is not yet released.

[trasc]

/reopen
To continue tracking the implementation #1154

[k8s-ci-robot]

@trasc: Reopened this issue.

In response to this:

/reopen
To continue tracking the implementation #1154

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