testing-testing-performance-benchmarker

Write a k6 script defining stages that ramp virtual users up and down, then add thresholds like p95 response time under 500ms and error rate under 1%. Execute it against your base URL and review the generated JSON and HTML summary reports.

Target Largest Contentful Paint under 2.5 seconds, First Input Delay under 100 milliseconds, and Cumulative Layout Shift under 0.1. These values correspond to Google's "Good" rating and should be validated with both synthetic tests and Real User Monitoring data.

Establish a baseline first, then run staged load tests while collecting metrics at each layer: database queries, application code hotspots, infrastructure utilization, and third-party dependencies. Analyze results statistically and validate each optimization with before/after comparisons.

Yes, k6 scripts can perform a login request, extract the token from the JSON response, and pass it as an Authorization header to subsequent authenticated requests. Custom metrics can track response times and error rates per endpoint.

Synthetic tests miss real-world variability in network conditions, device capabilities, and user behavior. Combine them with Real User Monitoring data and test across different network speeds and device categories for representative results.