LoopyLuci Error Budgets and SLO Management
Implementing error budgets and SLO management — from SLI definition through burn rate alerting, error budget policy, and reliability decision-making.
When to Use
- Setting SLOs for production services
- Managing error budgets between reliability and velocity
- Implementing burn-rate alerting
- Making data-driven reliability decisions
SLO Management
class SLOManager:
"""Track SLOs and error budgets with burn-rate alerts."""
def __init__(self, slo_target: float, window_days: int = 30):
self.slo = slo_target
self.window = window_days
self.total_events = 0
self.bad_events = 0
def record(self, total: int, bad: int):
self.total_events += total
self.bad_events += bad
def budget_remaining(self) -> float:
allowed_bad = self.total_events * (1 - self.slo)
consumed = self.bad_events / max(allowed_bad, 1)
return max(0.0, 1.0 - consumed)
def burn_rate(self, window_minutes: int = 60) -> str:
"""Burn rate alerting: budget consumed faster than expected."""
consumption_rate = self.bad_events / max(self.total_events, 1)
expected_rate = 1 - self.slo
if consumption_rate > expected_rate * 10: return "Critical: burn rate 10x"
if consumption_rate > expected_rate * 5: return "Warning: burn rate 5x"
if consumption_rate > expected_rate * 2: return "Notice: burn rate 2x"
return "Normal"
Verification Checklist
- SLIs defined for latency, error rate, throughput, availability
- SLO targets set per service tier (critical, standard, best-effort)
- Error budget window defined (30 days typical)
- Burn rate alerting configured (2x, 5x, 10x thresholds)
- Error budget policy documented (what happens when budget is exhausted)
- SLO dashboards visible to engineering teams
- Quarterly SLO review and adjustment process