Platform & DevOps·Placement, resources and the pod lifecycle
the sum of every limit on the node is three times the node, and it works fine until the day everything is busy at once.
Overcommit
Also calledoversubscription, burstable packing
Allowing the total of workloads' limits to exceed a node's real capacity, on the assumption that they will not all peak together. It is the mechanism that makes shared infrastructure economical, and it is a bet rather than a configuration. The bet loses in exactly the situation you care about — a correlated traffic spike — which is when eviction and throttling arrive together and the platform looks like it caused the incident.