Which of the following is usually identified by a performance test?

Performance testing is a non-functional test type designed to determine how a system performs in terms of responsiveness and stability under a particular workload. A primary goal of performance testing, particularly load and stress testing, is to measure, validate, and verify performance characteristics such as response times, throughput, and resource utilization. By pushing the system to its limits, testers can identify performance bottlenecks—components or resources (e.g., CPU, memory, database, network) that constrain the system's overall capacity and cause performance degradation.

B. Suitability issues: These relate to functional completeness and correctness for user tasks, which are evaluated through functional testing, not performance testing.
C. Learnability concerns: This is a sub-characteristic of usability, assessed through usability testing to determine how easily users can learn to operate the system.
D. Failure to meet accessibility requirements: This is evaluated via accessibility testing, which ensures the system is usable by people with the widest range of capabilities, including disabilities.

1. ISTQB® Certified Tester Foundation Level Syllabus (2018 V3.1.1)

Section 2.3.2

"Non-functional Test Types": "Performance testing is the process of testing to determine the performance of a software product... The goal of stress testing is to determine the robustness of the software product by testing it beyond the limits of its normal operation... A common use of performance and stress testing is to determine performance bottlenecks."

Source: ISTQB® Official Documentation. Available via ISTQB-approved member boards.

2. ISTQB® Glossary of Testing Terms:

Performance Testing: "The process of testing to determine the performance of a software product."

Bottleneck: "A component of a system that restricts the performance or capacity of the entire system."

URL: https://glossary.istqb.org/

3. ISO/IEC/IEEE 29119-1:2013

Software and systems engineering — Software testing — Part 1: Concepts and definitions

Section 8.2.5.3

"Performance testing": This standard defines performance testing as a type of testing conducted to evaluate the degree to which a system or component meets specified performance requirements. Identifying bottlenecks is an intrinsic part of this evaluation.

Source: IEEE Xplore Digital Library.