Metrics

• BudgetSourceUnavailable

  A metric source for an error-budget freeze or a promotion analysis could not be read.

• Error-budget freeze

  Freeze new-revision rollouts while a service is out of its SLO error budget, resuming on its own when it recovers.

• Metrics

  The controller's Prometheus metrics — the stageset_* custom series and controller-runtime signals, scraping with a ServiceMonitor or a plain config, querying with PromQL, and the chart values that drive them.

• Observability

  The four observability pillars for the controller — structured logging, OTLP tracing, Prometheus metrics, and the opt-in alert catalog — plus service level objectives and a ready-made dashboard.

• Operations

  Metrics, alerts, events, and runbooks for running the controller day to day.

• PromotionBlocked

  A stage's promotion analysis breached its thresholds, so the rollout will not advance past it.

• Reconcile latency high

  Reconcile p99 latency for the StageSet controller is above threshold.

• Service level objectives

  The StageSet controller's SLOs — reconcile availability and reconcile latency — with their SLIs, targets, error budget, the dashboard that shows them, and how to tune them.

• Workqueue saturation

  The controller cannot drain its reconcile queue fast enough.