Microservice Rate Limiting, Circuit Breaking, and Degradation: A Practical Guide from Avalanche Prevention to Fine-Grained Traffic Governance
Overview 3 AM, phone buzzing wildly. Open it — the alert group is already on fire. Payment service P99 latency jumped from 50ms to 12 seconds, error rate past 80%. Worse, the failure cascaded like dominoes: user service timeout → auth failures → inventory service retry storm → message queue backed up → payment callbacks all timed out. The monitoring dashboard went entirely red in thirty seconds. This isn’t a unique disaster....