Performance testing

Performance testing is a category of software testing concerned with evaluating how well a system behaves under various conditions, verifying that it meets the performance criteria specified in the user’s requirements.

Rather than checking functional correctness, performance testing focuses on qualities such as responsiveness, throughput, stability, and resource utilization. Performance testing may be used to ensure that an application performs not just under ideal conditions, but across a range of realistic and demanding scenarios.

Two of the most important techniques within performance testing are [load testing] and [stress testing], each probing the system’s limits in a distinct way. Load testing examines system behavior when subjected to higher-than-anticipated volumes of traffic or transactions, pushing the system beyond its expected operational limits to observe how performance degrades and at what point failures occur. Stress testing takes a similarly aggressive approach, subjecting the system to conditions beyond its normal operational capacity — whether in terms of concurrent users, data volume, or processing demand — in order to identify breaking points and assess how gracefully the system fails and recovers.

Performance testing techniques give development and operations teams a clearer picture of where bottlenecks lie, what headroom exists before degradation sets in, and whether the system can meet its performance obligations under the pressures of real-world use.