Choosing the Right Signal

• Logs: best when you need per-event detail — Logs capture individual events, making them ideal for deep debugging, security investigations, and audit trails. They allow you to reconstruct exactly what happened during a specific incident.
• Metrics: best for primary monitoring — Metrics provide aggregated numeric data over time, offering a strong balance between visibility and cost. They are ideal for dashboards, alerting, trend analysis, and overall system health monitoring.
• Tracing: best for understanding request flow in microservices — Traces show how a single request moves across services, helping identify latency bottlenecks, dependency failures, and performance issues in distributed systems.
• In practice, systems combine signals strategically — Most production environments use metrics as the monitoring foundation, complemented by targeted logging and tracing for deeper investigation when needed.