Load testing is a type of performance testing designed to evaluate the behavior of a system under varying loads. A primary objective of load testing is to observe how the system's performance metrics (e.g., response time, throughput) change as the load is progressively increased. This directly measures the system's ability to handle these increasing levels, typically from low to anticipated peak usage, to identify performance bottlenecks and ensure it meets specified performance objectives.

B. Elevation testing: This is not a standard or recognized term within the domain of performance testing. It is likely a distractor term, possibly confused with "privilege escalation" from security testing.

C. Spike testing: This test evaluates a system's ability to handle sudden, extreme, and short-term increases in load, not a gradual and sustained increase.

D. Endurance testing: Also known as soak testing, this evaluates a system's stability under a continuous, expected load over a long duration, checking for issues like memory leaks, not its response to increasing load.

1. ISTQB® Glossary of Testing Terms (Version 4.0):

Load Testing: "A type of performance testing conducted to evaluate the behavior of a component or system under varying loads

usually between anticipated low

typical

and peak usage." This definition's inclusion of "varying loads" directly supports the concept of testing with increasing levels of load.

Spike Testing: "A type of performance testing focused on a component's or system's ability to handle sudden

short-term

and extreme increases or decreases in load."

Endurance Testing (Soak Testing): "A type of performance testing conducted to evaluate the behavior of a component or system when subjected to a high load for a significant period of time."

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

2. Koomen

T.

van der Aalst

L.

Broekman

B.

& Vroon

M. (2006). TMap Next: For result-driven testing. UTN Publishers.

This foundational text on structured testing describes load testing as a method to determine the performance of a system under different load conditions

which inherently involves testing at various

often increasing

load levels to find the system's limits or performance profile. (Referenced in ISTQB syllabi).

3. Pressman

R. S.

& Maxim

B. R. (2020). Software Engineering: A Practitioner's Approach (9th ed.). McGraw-Hill Education.

Chapter 22

"Software Testing Strategies

" distinguishes between different performance tests. It describes load testing as executing a system in a manner that demands resources in increasing amounts

thereby aligning with the question's premise.