Analyzing telemetry — quick notes

Performance, in order: which operations are slow (p95/p99) → what are they waiting on (dependencies) → where in the code (traces).

• Skipping to code profiling answers the wrong question in detail.
• Aggregates hide people — segment by operation, region, version, tenant.
• A healthy global error rate can hide one customer failing every request.
• Correlate with release annotations — regressions usually follow a deployment.