LR Terminology_1

HP LoadRunner Terminology

 Scenario. A scenario is a sequence of events that emulate the hypothetical actions of real users on your application.

Vusers. In the scenario, LoadRunner replaces real users with virtual users or Vusers. While a workstation accommodates only a single human user, many Vusers can run concurrently on a single workstation. In fact, a scenario can contain tens, hundreds, or even thousands of Vusers.

 Vuser Scripts. The actions that a Vuser performs during the scenario are described in a Vuser script. When you run a scenario, each Vuser executes a Vuser script. The Vuser scripts include functions that measure and record the performance of your application's components.

Transactions. To measure the performance of the server, you define transactions. A transaction represents an action or a set of actions that you are interested in measuring. You define transactions within your Vuser script by enclosing the appropriate sections of the script with start and end transaction statements. For example, you can define a transaction that measures the time it takes for the server to process a request to view the balance of an account and for the information to be displayed at the ATM.

Rendezvous points. You insert rendezvous points into Vuser scripts to emulate heavy user load on the server. Rendezvous points instruct Vusers to wait during test execution for multiple Vusers to arrive at a certain point, so that they may simultaneously perform a task. For example, to emulate peak load on the bank server, you can insert a rendezvous point instructing 100 Vusers to deposit cash into their accounts at the same time.

Controller. You use the HP LoadRunner Controller to manage and maintain your scenarios. Using the Controller, you control all the Vusers in a scenario from a single workstation.

Load Generator. When you execute a scenario, the Controller distributes each Vuser in the scenario to a load generator. The load generator is the machine that executes the Vuser script, enabling the Vuser to emulate the actions of a human user.

Performance analysis. Vuser scripts include functions that measure and record system performance during load-testing sessions. During a scenario run, you can monitor the network and server resources. Following a scenario run, you can view performance analysis data in reports and graphs.

 

The HP LoadRunner Testing Process

General overview of the HP LoadRunner testing process.

1.   Planning the Test

2.   Creating the Vuser Scripts

3.   Designing the Scenario

4.   Running the Scenario

5.   Monitoring the Scenario

6.   Analyzing Test Results

Vuser types:

1. Protocol Based Vusers
2. Unit Test Based Vusers
3.  GUI Vusers

Vugen Recording Options:

• Script Section
• New Virtual User dialog
• Start Recording dialog

In Script Section, three sections of the script (vuser_init, Action, vuser_end) and running sequence.

On New Virtual User Dialog, This is the first step for script creation. VuGen provides option to create Single Protocol and Multiple Protocol script.

On Start Recording Dialog, fields with their valid input data. This is second step for script creation. From this dialog type of application, browser, URL, working directory, and “Record into Action” options are selected.

In Recording Option:

1. Scripts
2. Protocol
3. Recording
4. Port Mapping
5. Advanced Settings
6. Correlation
7. Code Generation

Script - This provides option to select the scripting language along with few settings related to the script. For Web (HTTP/HTML) protocol, the scripting language is C.

Protocol - This displays the protocol that we selected on New Virtual User Dialog box.

Script sections and different dialogs.  For Recording options, how to select scripting language and confirm the protocol that is going to be used while scripting.

• Recording – Selection of mode or http/html level can be done from this. URL and HTML mode of web (HTTP/HTML) protocol, which gives good understanding and idea about the major difference between them.
• Port Mapping- This provides option for Port Mapping.
• Advanced Settings- This covers few advanced settings related to script generation or script execution.
• Correlation- This is related to Automated Correlation. Correlation rules are created and enabled from this. In short, the fields available for the users on this dialog.
• Code Generation- This enhance the data format capabilities of web protocol.

Vugen Script Recording Summary:

• Protocol is the pre-requisite of script creation.
• Protocol Advisor is used to find the protocol that the application is using.
• Protocol Advisor is beneficial to performance testers by making the process of script creation faster and more focused.
• Transaction and its significance, functions used to create a transaction and how to capture response time of a request through them.
• Transactions are created to capture request of each action going to the server during script recording.
• A verification point in the form of text check is inserted before closing the transaction to confirm that the server is responding with the correct response. In case response is not as expected, the text check will fail, and that will fail the transaction also.
• The sample application that comes along with Vugen is used– Protocol Advisor and script recording through Vugen.
• For scripting modular approach is taken as it gives more control over the script.

Scenarios: Scenarios define the events that occur during each testing session. In LoadRunner, we can divide the performance testing requirements into multiple scenarios. Basically, a scenario defines and controls:

• Number of Vusers to emulate
• Actions that they perform
• Machines on which they run

Vusers: Vuser as the name implies – Virtual User. LoadRunner replaces human users with Vusers. During a scenario run, Vusers emulate the actions of human users to the server and the application. A scenario can contain multiple Vusers like tens, hundreds, or even thousands.

Vuser Scripts: Vuser scripts describe the actions to be performed by Vuser during the scenario run. During a scenario run, Vuser execute Vuser script which include functions to measure the performance of the server during that particular scenario.

Transactions: Transactions are defined in the Vuser script to measure the performance of the server. These are defined to capture the response time taken by the server for the task.

Rendezvous Points: Rendezvous points instruct multiple Vusers to perform a task or set of tasks at the same time to emulate a heavy user load on the server.

Controller: Controller is used to manage and maintain the scenarios from a single workstation.

Hosts: Host is a machine used to execute the vuser scripts. It enables the vusers to emulate the actions similar to a human user. At the time of scenario execution, the LoadRunner Controller distribute Vusers in the scenario to hosts.

Performance Analysis: A Vuser script includes functions that measure the system performance during load testing sessions. Network and server resources can be monitored during the scenario run. After the successful run of a scenario, performance analysis data can be viewed in reports and graphs.

References: 1). claudihome.com/html/LR/ (HP Site)    

2). softwaretestinghelp.com

3). loadrunnerstuff.com

  
Note: Some of the articles are grab from various Websites / Blogs.