Scale-up Policy for PodDisruptionBudget

[chansuke]

Enhancement Description

• One-line enhancement description (can be used as a release note):
  • Add an optional Scale-up Policy to PodDisruptionBudgetSpec that allows the Disruption Controller to temporarily increase replicas—via the /scale sub-resource—so that voluntary evictions or node drains can proceed even when minAvailable would otherwise be violated.
• Kubernetes Enhancement Proposal:
• Discussion Link:
  • https://kubernetes.slack.com/archives/C09R1LV8S/p1746298062727629
• Primary contact (assignee):@chansuke
• Responsible SIGs: sig-autoscaling
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y):
  • Beta release target (x.y):
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s):
  • Code (k/k) update PR(s):
  • Docs (k/website) update PR(s):

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

[chansuke]

cc: @x13n

[chansuke]

/sig autoscaling

[x13n]

/cc @atiratree

We need to figure out how this is related to #4563 so we don't end up with two completely different mechanisms to solve the same problem.