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cfsthrottle

confirmedKubernetes · minikubeCluster & infrastructureJuly 8, 2026

the question

Does a Kubernetes CPU limit inflate tail latency?

what came out

Badly -- a 60ms-CPU request's p99 balloons to 9.7x at a 100m limit, tracking the cgroup's throttled time and vanishing when the quota fits the burst, while the pod uses under 6% of the node. CFS per-period throttling. Real minikube (cgroup v2), pre-registered, independently verified.

method & receipts

  • Result: confirmed
  • Pre-registered the prediction was written down and committed before the run.
  • Reproducible one script re-runs the whole thing from scratch.
  • Independently reviewed an adversarial review pass, kept in the repo.
  • Machine-readable claims every reported number, in a checkable file.
  • Tested — a correctness/benchmark suite ships alongside the code.

→ read the code and re-run it

github.com/v-code01/cfsthrottle