Once you have a TestPlan configured the way you want it, running it is as simple
as selecting Run->Start from JMeter's menu. To stop, choose Run->Stop from the menu.
While JMeter is running, you can select any visualizers you've added to watch the
results while samples are collected. You can flip between visualizers to get
different views of the data. Visualizers can be cleared of all current data via the
Run->Clear menu option.