qos

The pair everyone configures and few can explain. QoS hints at eviction risk, but usage versus requests and Pod priority determine node-pressure ranking, and CPU and memory behave completely differently when you exceed them.

Priority is one number with three separate effects: scheduling order, preemption victim selection, and eviction order under node pressure. Conflating those is the trap; designing tiers that survive both a full cluster and a hot node is the pass.