Observability — OpenTelemetry & Distributed Tracing Instrumentation moderne avec OpenTelemetry pour métriques, traces et logs structurés. Piliers de l'Observabilité | Pilier | Technologies | Métriques clés | |--------|--------------|----------------| | Metrics | Prometheus, Grafana, Datadog | RED (Rate, Errors, Duration), USE (Utilization, Saturation, Errors) | | Traces | OpenTelemetry, Jaeger, Tempo | P95 latency, span duration, error rate | | Logs | Loki, ElasticSearch, Datadog | Structured JSON, correlation IDs | OpenTelemetry (OTel) Stack Golden Signals (Google SRE) | Signal | Description…