Ydelsestests

Ydelsestests, or performance testing, is a form of software testing focused on how a system behaves under expected and peak workloads. The goal is to assess speed, responsiveness, stability, and resource usage to ensure the system meets defined performance criteria.

Performance criteria are typically expressed as service level objectives (SLOs) and may include target response times, maximum throughput, and acceptable error rates. Key metrics include average and 95th percentile response time, requests per second (throughput), concurrency, CPU and memory utilization, disk I/O, and network latency.

Common test types include load testing, which measures behavior under planned user load; stress testing, which pushes beyond expected load to determine limits; soak or endurance testing, which runs for extended periods to reveal leaks; spike testing, which examines responses to sudden increases; and scalability testing, which evaluates performance as resources are added.

Process: define objectives and acceptance criteria; design realistic scenarios; prepare a representative test environment and data; execute tests; collect telemetry; analyze results and identify bottlenecks; implement optimizations; re-test to verify improvements. Documentation and baselines are essential for capacity planning.

Tools and practices: popular tools include JMeter, Gatling, Locust, and k6; monitoring with Prometheus, Grafana, or commercial APM solutions helps correlate software behavior with system resources. Ydelsestests are part of performance engineering and continuous delivery, requiring careful environment management to avoid misleading results.