Add number of AdmittedWorkloads to LocalQueue status

[alculquicondor]

What would you like to be added:

A field containing the number of active workloads.

We abandoned this idea earlier because the cache was not queue aware. But we already need to make it queue aware for the purpose of metrics #199

Why is this needed:

Improve UX around observability

/kind ux

Completion requirements:

This enhancement requires the following artifacts:

• Design doc
• API change
• Docs update

The artifacts should be linked in subsequent comments.

[nayihz]

The active workloads are the workloads which have been admitted by scheduler. Do I understand it correctly?

kueue/pkg/scheduler/scheduler.go

Lines 304 to 308 in afabae9

	newWorkload.Spec.Admission = admission
	if err := s.cache.AssumeWorkload(newWorkload); err != nil {
	return err
	}
	log.V(2).Info("Workload assumed in the cache")

[alculquicondor]

not assumed, but actually part of the cache. But please don't work on this yet. I'm working on a change to add the metric with the same data. We can reuse that code to include it in the status.

[alculquicondor]

I did some progress on this #259. After it merges, feel free to take over.

[ahg-g]

This would be similar to the AdmittedWorkloads in ClusterQueue

[ahg-g]

/assign @kannon92

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[kannon92]

/assign @kannon92

[kannon92]

I am getting up to speed in this repo.

AdmittedWorkloads is the same as ActiveWorkloads?

[ahg-g]

yes, we are using the term admitted now.

[kannon92]

Hello. So I made progress on this but I realize I'm unclear on the ask. The issue reads very simple as add a new field.

So here is my research:

1. Add a new field for AdmittedWorkloads in Apis
2. Update the CRD to reflect the new field

If I read the ticket exactly, then I believe my work is done?

Is the intent that future features will update this API field? Or should I also tackle this as part of the issue?

[ahg-g]

Not only add the field, we need to do populate it as well. Kueue is the one responsible for updating the status of both LocalQueue and ClusterQueue. Take a look at the AdmittedWorkloads field in ClusterQueue and how we populate it as an example.

[kannon92]

Sounds good! I am making progress on this. Do we want these fields as added into metrics also?

[alculquicondor]

No, we actually did that initially and reverted the change #293.

Just the status field should be good.

[kannon92]

Alright. I think I have something for you all to review. #382

Sorry about the spamming the repo with a few opens.