Key Performance Metrices in Microservices Architecture

🔹 1. Infrastructure & Platform Metrics

Track system health and scalability.

• CPU, Memory, Disk, Network Utilization → To ensure pods/containers are not resource-starved.

• Container & Pod Restarts (Kubernetes) → Indicates stability issues.

• Autoscaling Effectiveness → How well HPA (Horizontal Pod Autoscaler) or cluster scaling is reacting.

• Error Events (K8s, Istio, etc.) → CrashLoopBackOff, OOMKilled, etc.

🔹 2. Service-Level Metrics (Golden Signals from SRE)

These are Istio/Envoy + App telemetry based.

• Latency (p95, p99) → Response time of each service/API.

• Traffic → Number of requests per second (RPS), throughput (QPS).

• Errors → 4xx (client issues), 5xx (server failures), gRPC errors.

• Saturation → Queue depth, thread pool usage.

🔹 3. Application Metrics

• API Success vs Failure Rate → Helps in SLA/SLO tracking.

• Dependency Latency → DB queries, Kafka topics, downstream services.

• Circuit Breaker Metrics (Istio/Resilience4j) → Open/half-open states, retries.

• Cache Hit Ratio (Redis, CDN) → Efficiency of caching strategy.

• DB Metrics → Slow queries, connection pool utilization, replication lag.

🔹 4. Reliability & Resilience Metrics

• MTTR (Mean Time to Recovery)

• MTBF (Mean Time Between Failures)

• Service Availability (uptime %)

• Request Retry Count & Fallback Usage

🔹 5. Security Metrics

• Auth/Token Failures (OAuth/JWT/OPA)

• mTLS handshake failures (Istio)

• Unauthorized access attempts

• Vulnerability scan & patch compliance

🔹 6. Business & Domain Metrics

Directly tied to business outcomes.

• Transaction Success Rate (e.g., successful payments/loans approved).

• User Onboarding Conversion Rate

• Revenue-impacting Latency (checkout, payment APIs).

• Abandonment Rate (loan journey drop-offs).

• Fraud Detection Accuracy (false positives/negatives).

🔹 7. Observability & Tracing Metrics

• Distributed Tracing (Jaeger/Zipkin/Tempo) → End-to-end latency.

• Log Volume & Error Patterns (ELK, Loki, Splunk).

• Service-to-Service Dependency Graph (Istio Kiali).

✅ In practice, you should track a combination of Golden Signals + Business KPIs.

• Golden Signals (Latency, Traffic, Errors, Saturation) → For SRE/DevOps.

• Business KPIs → For Product/Management.