Opportunistic Use

In 95% of cases you don’t need to set priorityClassName. The only common reason to set it is to use A100 / H100 / H200 / GH200 GPUs without a reservation, by setting priorityClassName: opportunistic.

What you’re allowed to set

Everything else (default, owner, nice, batch-low, system-*, kubevirt-*, *-batch-high, etc.) is banned in user namespaces. If your tooling auto-sets one of these, remove that line — your pod will run at the unset default, which is what you want. Exemption requests for legitimate cases go through Matrix.

Using opportunistic for special GPUs

apiVersion: v1
kind: Pod
metadata:
  name: h200-opportunistic
spec:
  priorityClassName: opportunistic
  containers:
  - name: gpu-container
    image: nvidia/cuda:12.4.1-cudnn-devel-ubuntu22.04
    command: ["python", "train.py"]
    resources:
      limits:
        nvidia.com/h200: 1
      requests:
        nvidia.com/h200: 1

The pod can be preempted by any other pod in the cluster, so checkpoint frequently or run it as a Job so the controller can restart it.

opportunistic2 is the same idea but sits one step above opportunistic in priority — useful only if you don’t want to be preempted by other opportunistic workloads.

If your pod is rejected

pods "..." is forbidden: exceeded quota: high-priority-ban or low-priority-ban means your priorityClassName is on the ban list. Drop the field or switch to one of the allowed classes above.