Load testing is one of several different kinds of Performance related tests (Load Testing, Stress Testing, Spike testing, Endurance testing, Scalability Testing, Volume testing). In a sense of usage all of them are related to Performance Testing definition, which in one sentence, would be:

“Performance Testing is artificially creating or simulating load and measuring how your environment handles it.”

Load testing provides system monitoring by increasing the load. You can test how the system performs under higher load, but also under base or expected load. During Load Tests you can monitor response times, throughput, server condition and much more.

The goal of Load Testing is not to break the target environment, but to measure performance parameters under high load.

WAPTpro

WAPTpro is one of several Load testing tools that can be used for this purpose. It provides interface for testing performance parameters of a websites and web-based internet applications.

Create Scenario

To perform Load testing for a website with WAPTpro, first you need to create a test Scenario with general parameters for the test: number of virtual users, type of load, test duration or the total number of sessions for all virtual users. This can be obtained in Scenario Wizard that you can open by click on a New button in a upper left corner of the WAPTpro window. Later, these settings can be changed by clicking on a Test Volume menu item in a left section of WAPTpro window.





scenario wizard2


scenario wizard3


scenario wizard1

Depending on your test goal and what you want to find out about your site or application, you can choose three types of load in Scenario Wizard:

  1. Constant:

Test will have constant number of simultaneously started users.

  1. Ramp-up:

Increasing number of users. The number of users will increase until it reaches maximum value which you have set. Also, you can set a delay before starting the next user(s).

  1. Periodic:

Periodic load has 2 phases with low and high load level which are changing one another during the test. You can specify the number of users for each phase and set the duration of it.

Create virtual user Profile and record the first test

After you have set scenario parameters and clicked Finish button in Scenario wizard, you will automatically be proceed to Recording Options dialog:

recording options

  1. Beside browser options, the dialog provides option for the new Profile creation which will ensure that  virtual user Profile is created.

To setup load test, you will need to record a sequence of real user actions (for a single user session) on the site which you want to test. This set of user actions (page requests) makes one user Profile recorded by WAPTpro Recorder. User profile describes the behavior of virtual users which number will be increased by WAPTpro during the test run. When test run, WAPTpro will create a copy of the recorded session which will be repeated by many virtual users running simultaneously.

  1. Recording will be done with the chosen browser. By default WAPT pro uses Internet Explorer which is embedded with it, but you can choose one of the external browsers as well. You can create as many profiles as you need. Recording can be done from a browser running on a same or different computer. If browser runs on a different computer, important thing is to obtain connection between your browser and the computer where WAPTpro is running.
  2. To ensure that profile will be recorded and later executed properly, you need to delete browser cache and cookies. WAPTpro can do this for you if you had chosen Internet Explorer for the recording browser and left these two checkboxes checked. Otherwise, if you chose external browser,  WAPT will not do this for you. In this case, to obtain clean session it is important to do it yourself.

The Recording Options dialog will open after scenario parameters are set and you should record your first test. Otherwise, the new Profile can be created separately by clicking New button from the toolbar and choosing Profile as an option.

new profile wizard

To record user actions for this Profile you need to click Rec button from the address bar. This way you will get the same  Recording Options dialog for the newly created Profile.

After you click OK button in a Recording Option dialog, the recording will start. WAPT will open chosen browser for you and you will be able to start with navigation through the site you want to load test.

When you have got desired set of requests you can click on a Stop Rec button in a toolbar and finish the recording process.

toolbar_recording

In WAPT left section, under Profile menu item you will see the list of the requests that you have just recorded.

left_navigation_window

 

In its recording process WAPTpro is acting as an HTTP proxy between your browser and the web site you want to test. By default WAPTpro proxy IP address is set to 127.0.0.1 (localhost). In order to be visible to your site, first you need to change it in a Recorder settings dialog which can be reached by click on Settings button and Recorder tab (Recorder Proxy section). In a drop down list you can choose one of additional addresses that will be displayed if WAPTpro is connected to a network.

recorder

 

This is where you will meet the problem in a case that you want to test HTTPS site for the first time. With HTTPS the information is passed encrypted and HTTPS makes impossible for anyone in the middle to read the information. So, the WAPTpro needs to act in a way that browser thinks that encryption performed by WAPT is done by the site, and the site thinks that it gets data encrypted by the browser. In this situation WAPTpro has to decrypt and encrypt the information. To make it behave like desired you need to add WAPT recorder certificate called “Trusted Root Certification Authorities”.

When you try to record an HTTPS profile for the first time, WAPTpro will try to install that certificate by default. Manually, this can be done in Settings dialog, HTTPS tab, View/Install Certificate button. Setting dialog can be reached by click on Settings button:

certificate_import_wiz1

 

certificate_import_wiz2

 

Test Verification

Before you run the test in WAPTpro you have option to check if the Profile(s) you would like to run have any errors. This can be done by clicking Verify Test button from toolbar. It will open the dialog with available Profiles where you can select which Profile(s) you would like to check.

verify_test_btn

All selected profiles will be executed once with a single user and without delays for each of them. WAPT will use the first Load Agent checked in the list of Load Agents for the verification tests.

When test verification is done, the simple Summary Report located in a left side of WAPTpro window, under Results menu item, will be generated.

Run the Test

After you created Scenario, added user Profile with the recorded set of requests you would like to emulate in your test, as a final step you will need to add one Load Agent to start a test. Load Agent is a component that emulates the test scenario and executes the test.

 

It can be installed on your local computer, on any computer in the Local Area Network, or on a remote server anywhere in the Internet. For the correct work of Load Agent you will need to add certain settings during the installation. Later, it can be changed in the Load Agent Manager.

 

Load Agent Manager is located on your system: Start menu > SoftLogica > WAPTpro > Load Agent Manager.

load_agent_manager1

Here you can change the state of Load Agent and change account for it. If you click on Change account button, you will get next dialog:

load_manager2

 

Here you can specify another account for the Load Agent service. You can choose the Local System account or provide a username and password for any other one. Account name should have the domain\username format.

Now, when everything is set, you can run your test by clicking Run Test button in toolbar. You will get your first results right after test has started. The Performance window will be displayed in a right side of WAPTpro window.

When test is finished, you will get test results in a form of text report and graphs.

 

Test results and its analyzing will be next blog topic.

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