Using timers in your test plan
By default, JMeter doesn't put timers in your test plans when a scenario is recorded. This is far from reality. Ideally, users will have a think or wait time between page views and requests. Getting JMeter to simulate such pauses or waits makes your test plans more realistic, bringing them closer to how actual users may behave. JMeter offers various built-in timer components that help achieve this. Each varies from the others in how it varies the simulated pauses. The following is a list of some of the included timers at the time of writing of this book.
The Constant Timer
The Constant Timer is used if you want each thread to pause for the same amount of time between requests.
The Gaussian Random Timer
The Gaussian Random Timer pauses each thread request for a random amount of time, with most of the time intervals occurring near a particular value. The total delay is the sum of the Gaussian distributed value times, the value specified, and the offset.