Website Performance Testing Tools, Apache JMeter

How JMeter Works?

The basic workflow of the JMeter can be seen in the image below:



First, the user sends the request to the target server. Then, it gets the useful information of the target server and provides you with the results in different formats, such as Graphics, Chart, and Tree.



The demonstration of the JMeter testing tool:

Step 1: We can download the Apache JMeter testing tool form this site.

If you click this link, a new window will open. There, you can download the file, as highlighted in the following image. It’s a zip file.



Step 2: Once the download is complete, extract the file in your system.

Step 3: Now, you can run this tool, but first, you need to check the version of Java. If you don’t have version 7 installed, the application will not work.

Step 4: Open the Bin folder and search for the JMeter file (It will be Windows batch file). Now, click open this file.




Step 5: When you start the JMeter, you will see two branches in the left pane, Test Plan and Workbench.

Test Plan is the place where your tests will go live. A complete test plan can contain one or more threads, groups, listeners, timers, and configuration elements.

Workbench, however, is the place where the tests are stored temporarily while they are run. JMeter throws away the content of workbench, upon exit. So, JMeter only saves the content of the Test Plan branch, not the Workbench.



Step 6: Now, the next step is the configuration of the Tree elements. In Test Plan, any element can be configured using the control panel. Just right click on the Test Plan, go to Add >> Threads (Users) >> Thread Group.

A Thread Group is the beginning point of your Test Plan that controls the number of threads used by JMeter during the test. Thread Group has some properties, as listed below:

• Number of Threads (users) simply means the numbers of users that can be added.
• Ramp up Period (in seconds) means how much time this tool (Apache JMeter) should take to get all the threads started.
• Loop Count means how many times the test case will be performed for each thread.

Step 7: Now, the next step is to work on Controllers. Basically, there are two types of controllers - Sampler & Logic. Here, we will discuss the Sampler only.

Just right click on the Thread Group and go to Add >> Sampler >> HTTP Request.

Sampler is nothing but the medium that allows the send requests on a server when a user requests for a page from the server. There are a lot of useful samplers, including HTTP & FTP Request, JAVA & JDBC Request and RPC Requests. We are using only HTTP Request.





In HTTP request, you can write any Server name or IP address that you want to test. For example, www.facebook.com, or www.google.co.in, or even www.c-sharpcorner.com. Remember one thing. You don't have to write http in the URL of the Server.



Step 8: Now, the next step is to use the Listeners for viewing the results in the form of tree, graphs, and table, and also, for providing the visual access of the data gathered by JMeter.

Listener can be added anywhere in the test. JMeter provides a lots of Listeners, such as, View results in Table, Graph results, Monitor results etc. Just right click on the Thread Group and go to Add >> Listener >> View results in Table.

We are using View Results in Table and Graph Results, only.



Now, you get the following screenshot A where you get the results in Table View after running your Test Plan. If you want to remove all the results from the table, just use the Clear All Button, as shown in screenshot B.





Now, let's discuss the Graph Results.

Right click on the Thread Group and go to Add >> Listener >> Graph Results.



Now, you will see the results in graphical form.



The graph of results is displayed in the form of Data, Average, Median, Deviation and Throughput. Let us discuss it point to point.

• DATA means the plotting of actual data values ( represented in the above image in Black).
• Average means average time of a set of results (in Blue).
• Median divides the samples into two equal halves.
• Deviation measures the variability of a data set (in Red).
• Throughput means the plotting of the samples per unit of time (in Green).

So, this is how we can test a website, using JMeter, in order to increase the performance, reliability, and the speed of it.