slo-and-error-budgets

name	slo-and-error-budgets
description	Design SLIs/SLOs and an error-budget policy: pick user-centric indicators, set targets by user need (not 100%), define the ship-vs-freeze budget rule, and enforce with multi-window multi-burn-rate alerts.

SLOs & Error Budgets

Purpose: decide how reliable a service must be and enforce it.

SLIs

Measure user happiness at the boundary: availability, latency (p99), correctness. good events / valid events.

SLO target

Set by user need. 99.9% = ~43 min/month budget. 100% is a cost, not a goal.

Error-budget policy

• Budget remaining -> ship features, take risk.
• Budget exhausted -> freeze features, do reliability work.

Burn-rate alerting (multi-window)

Page when burning fast and confirmed: e.g. 2% budget in 1h (fast) AND sustained over 5m. Multi-window suppresses blips, catches real fast-burns.