JMX is a file extension used by a software tool called Apache JMeter. It is a solution that allows you to carry out tests that allow you to determine what loads can be dealt with by a server providing services in the network, e.g. www, databases, ftp, web applications. This may include, for example, downloading static and dynamic content.

JMX are files used to store data used for internal purposes of the program. JMeter is normally run in a graphical environment, but it can also be run outside the GUI. In command mode, the command that runs this tool might look like this: sh jmeter -n -t /home/user/test.jmx