LoadRunner

Introducing Mercury LoadRunner

Download Full Article

Mercury LoadRunner.ppt
LoadRunnerQuickStart.pdf

LoadRunner is a tool used to emulate an environment where multiple users work concurrently. While the application is under load, LoadRunner accurately measures and analyzes the system performance, and its functionality

LoadRunner Terminology

Scenarios
Using LoadRunner, you divide your application performance testing requirements into scenarios.
A scenario defines the events that occur during each testing session.
For example, a scenario defines and controls the number of users to emulate, the actions that they perform, and the machines on which they run their emulations.

Vusers
In the scenario, LoadRunner replaces human users with virtual users or Vusers.
When you run a scenario, Vusers emulate the actions of human users—submitting input to the server.
A scenario can contain tens, hundreds, or even thousands of Vusers.

Hosts
When you execute a scenario, the LoadRunner Controller distributes each Vuser in the scenario to a host.
The host 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.

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 the server during the scenario.

Transactions
To measure the performance of the server, you define transactions.
Transactions measure the time that it takes for the server to respond to tasks submitted by Vusers.

Rendezvous Points
You insert rendezvous points into Vuser scripts to emulate heavy user load on the server.
Rendezvous points instruct multiple Vusers to perform tasks at exactly the same time.
For example, to emulate peak load on the bank server, you insert a rendezvous point to instruct 100 Vusers to simultaneously deposit cash into their accounts.

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

Mercury LoadRunner Components

• Virtual User Generator (VuGen)
• LoadRunner Controller
• LoadRunner Analysis

Steps in LoadRunner Testing Process

Plan the test
Create Vuser scripts
Create controller scenario
Run the scenario
Monitor the scenario
Analyze the results

LoadRunner Virtual User Generator

Section of Script

Vuser_init
Action
Vuser_end

Developing Vuser Scripts

Walk through the scenario to be scripted
Record the scenario
Edit or enhance the script
Configure the runtime settings
Run the Vuser script
Re-enhance and re-run till working properly
Incorporate the script into LR scenario

 Scripting:

• Mainly ‘C’ Programming Language Based
• Able to incorporate ‘C’ looping structures (for, if, while,…)
• Can also use Java, JavaScript, VB and VBScript

Script Enhancements

Transactions
Parameterization
Rendezvous Points
Think Time

Defining User Behavior

Recording Options

Recording
Browser
Recording Proxy
Advanced
Correlation

Runtime Settings       

General
Network
Browser
Internet Protocol

Mercury LoadRunner Controller

New Scenario:       

Manual Scenario
1.  Percentages Option
Goal Oriented Scenario



Configurations on Design Tab

Edit Schedule
Setting Up the Rendezvous (If Any)
Runtime Settings
Load Generators
No of Vuser per Script

Configurations on Run Tab

Select a Graph from the Available Graphs Tree
Drag and Drop it in the Graph View Area to View
Graphs Available by Default
Runtime Graphs
Transaction Graphs
Web Resource Graphs
Other graphs have to be configured by add measurements that can be monitored.

Mercury LoadRunner Analysis

<

Analyzing test results

1. During scenario execution, LoadRunner records the performance of the application under different loads.
2. You use LoadRunner’s graphs and reports to analyze the server’s performance. LoadRunner’s default graphs and reports are divided into the following three categories:
a. Runtime Graphs
b. Transaction Graphs
c. Web Resource Graphs

Runtime Graphs and reports provide information about the number of Vusers and the number of transactions executed during the scenario run
Transaction Graphs and reports analyze Vuser performance and transaction times.
Web Resource Graphs provide information about the throughput and connection times of Web Vusers.

Viewing a part of scenario

1. You can instruct LoadRunner to calculate graphs and reports based on a part of the scenario.
2. For example, if you have a scenario with a duration of 400 seconds, but you are only interested in the period beginning at 60 and ending with 360 seconds, you can specify that interval in the Time Filter dialog box.
3. After setting the time filter, you must rebuild the result database in order for the changes to take effect.

Working with Analysis Graphs

LoadRunner also provides tools which enable you to modify the way that graphs are displayed. For each graph you can:
a. View Specific Transactions and Vusers
b. Enlarge a Section of a Graph
c. Change the Granularity of the X-axis for a Graph

d. Merge Graphs to compare them
e. About Scenario Activity

Running Virtual Users Graph

The Running Virtual User graph displays the number of Vusers that executed Vuser scripts during each second of a scenario run. This graph is useful for determining the Vuser load on your server at any given moment. The x-axis represents the elapsed time (in seconds) since the start of the scenario run. The y-axis represents the number of running Vusers in the scenario

Transactions per Second Graph (Passed)

The Transactions per Second (Passed) graph displays the number of completed, successful transactions performed during each second of a scenario run.

Transaction Response Time (Percentile)

Transaction Response Time Under Load Graph

The Transaction Response Time Under Load graph indicates transaction response times relative to the number of Vusers running at any given point during the scenario.

Hits Per Second Graph

Displays the number of hits made on the Web server by Vusers during each second of the load test. This graph helps you evaluate the amount of load Vusers generate, in terms of the number of hits.

Throughput

Displays the amount of throughput (in bytes) on the Web server during the load test. Throughput represents the amount of data that the Vusers received from the server at any given second. This graph helps you to evaluate the amount of load Vusers generate, in terms of server throughput.

Server and Network Graph(s)

Depending on the measurements selected and the server selected LoadRunner produces graphs based on them.
Sample: Weblogic and Oracle

Download Full Article

Mercury LoadRunner.ppt
LoadRunnerQuickStart.pdf

You Should Also Check Out This Post:

• Factors influencing Acceptance Testing
• Rational Suite of tools
• Test Report
• System Testing Techniques
• System Testing

More Active Posts:

• Test Effort Estimation (3)
• Defect Tracking Tools Comparison (2)
• Manual Testing (1)
• Software Testing (1)
• Performance Testing Tools Features (1)
• Apache JMeter (1)
• LoadRunner (1)
• Testing Methods (1)
• Terminologies in Software Testing (1)
• Whitebox Testing (1)