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Priority and preemption

A node is full and an important pod was just created. Does it hang Pending behind the junk pods, or does it get to kick out a less important pod to grab the spot? PriorityClass assigns a priority level; preemption lets a high-priority pod evict low-priority pods when needed. This article fills the cluster with low-priority pods, then drops in a high-priority one — watch it kick out the victim and take the spot, exactly the PostFilter step Article 34 called 'not helpful'.