Make it easy to describe the preempting workload

[avrittrohwer]

What would you like to be added:

Make it easy to kubectl describe the workload that evicted another workload.

Why is this needed:

Kueue Workloads have events like kueue-admission Preempted to accommodate a workload (UID: <UID>) due to fair sharing within the cohort

As far as I can tell kubectl --selector field only supports filtering on values in the object .metadata.labels. The Workload UID is in the .metadata.UID field which can not be filtered on by kubectl --selector. For clusters with few workloads grepping on kubectl get workloads -A would work but does not scale for clusters with thousands of workloads.

Completion requirements:

Make it easy to kubectl describe the Workload that preempted another workload. Simple solution: add the Workload UID to the Workload labels.

This enhancement requires the following artifacts:

• Design doc
• API change
• [ x] Docs update -> add docs on how to get details of preempting workload.

The artifacts should be linked in subsequent comments.

[kannon92]

Have you looked at kueuectrl? maybe the UX would be better using the CLI?

[mimowo]

I don't remember if kueuectl would allow it, probably not. However, in any case as an external binary the only way to find the preempting workload by UID would be to list all workloads first, which is not scalable indeed.

I like the idea of adding the UID as a label. cc @tenzen-y WDYT?