What is Performance Testing

Definition

Performance testing evaluates how a system behaves under various conditions, measuring response time, throughput, and resource use to determine whether it meets speed and scalability requirements and to uncover bottlenecks before they affect real users.

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Measures response time and throughput against defined requirements
Uncovers bottlenecks before they degrade the user experience in production
Informs capacity planning and scalability decisions with real data
Reduces the risk of slowdowns and outages under real-world demand

Real World Example

Before a product launch, a team runs performance tests that measure response times as concurrent users increase, identifying a database query that degrades under load and optimising it before customers arrive.

FAQs

What does performance testing measure?

It measures response time, throughput, and resource utilisation to assess whether a system meets its speed and scalability goals.

How is it different from load testing?

Load testing is one type of performance testing focused on behaviour under expected and peak load; performance testing is the broader category.

Why test performance before release?

To find and fix bottlenecks proactively, avoiding slowdowns or outages once real users generate demand.