What is the purpose of the JMeter Loop Controller?

The purpose of the JMeter Loop Controller is to repeat a set of test steps multiple times in a test plan. It can execute loops based on user-defined conditions to simulate concurrent user behavior.

A loop controller can be used in the following scenarios:

1. Perform a set of test steps repeatedly to simulate the actions of multiple concurrent users.
2. Repeat the execution of a test step until a specified condition is met, such as reaching a certain number of requests or continuing for a certain amount of time.
3. Simulate user iteractions, such as logging in, performing a series of actions, logging out, and then starting the cycle again.

Using the loop controller, it is possible to have more flexibility in controlling the execution times and concurrency levels of the test plan, in order to perform more comprehensive and efficient performance testing on the system.