Sunday, June 10, 2012

LoadRunner Interview Questions with Answers

1)What is rendezvous point.
To emulate peak load on the server.
This function is used to stress a particular element of the infrastructure, for example you might want to design a test where 100 vusers simultaneously hit a button to transfer some funds.
Rendezvous points instruct Vusers to wait during test execution for multiple Vusers to arrive at a certain point, in order that they may simultaneously perform a task.
2)What are the load runner testing process .
There are 5 steps.
1.Test requirements
2.Test planning.
3.Test Automation(Script).
4.Test execution.
3)What is vugen?
It is a load runner vuser script generator(use for recording the data base vuser script )
It is used to generate and enhance the vuser business script for all the scenarios which are in scope.
vuGen is a virtual user generator which is used to record the scripts for single user only.

4)How you edit the script .
While editing the script we have to inserting the transaction point and rendezvous point .
Recorded script which contains the interaction between the client and server is edited by added the following :

1. Parametrization
2. Correlation
3. Transactions (Start/End)
4. Validations
5. Rendezvous point
6. Variable Declarations
5)What is the load runner start-transaction and its syntax.
It will start the transaction on the script. syntax. Lr-start-transaction("transaction name").
Syntax: lr_start_transaction("transaction name");

For ex: lr_start_transaction("Launch_Application");

This function starts recording the traffic response time between the client and server until it find its lr_end_transaction.
6)What is the load runner end transaction and its syntax.
It will end the transaction. syntax. Lr-end-transaction("transaction name", lr-auto).

Syntax: lr_end_transaction("transaction name", LR_AUTO/LR_PASS/LR_FAIL);

This function stops recording the time between the client and server.

lr_start_transaction("Transaction name",LR_AUTO);
Can lr supports autocad 2011 application version. We are tryig to invoke application using lr,but the tool is getting hanged. We can open the application manually.Please help us is resolving the issue.

7)How to call winrunner script in loadrunner?
1.Create a scenario by replacing the VUser script with the GUI WinRunner script.
2.Select Host->Details options from menu
3.Enable the check box for GUI Winrunner(Mandatory to run the WR Script)
8)What are the the types of parametrization in load runner?

There are various types of parametrization in Load Runner. They are
1. Date
2. Random Number
3. Unique Number
4. File

9)What are the steps for doing load and performance testing using load runner?
1) Select the load Runner from the Start menu.
2) From the Load testing Tab, click on "Create/Edit Scripts"
3) Once the Virtual User generator is opened, select "New" and select the protocol based on your project requirement or for a sample application select "Web(HTML/HTTP)" protocol from the Available protocols and click "ok"
4) Enter the URL of the application which you are going to test.
5) Give the Working Directory path in which your script need to be saved.
6) In Record to Action you have three options
i) vuser_init -> record the login part
ii) Action -> record the transaction or the body part.
iii) vuser_end -> record the sign off
Note: for your sample login to action and record all the script.
7) Once the url is opened start entering the username and password and do the other transaction process. Once finish, log off and stop the record session by click the stop icon.
8) Correlate the script, parameterize the URL, username and password if required other variables too and check whether the the script runs without any errors
Note: Before running check the run time settings and run for atleast three to five iterations.
9) Create more scripts according to your requirement and check they should run without errors.
10) Open the scenario, pull all the scripts add the number of users you want to run, set the rampup and duration of the run. Runtime settings and Generators you are using to run the load should be given. see that you connected the generators and Start running the scenario.
11) Analyse the graph for the performance.

10)How to run a scenario.
Open an existing scenario . configure the scenario. set the result directory. run the scenario.
Steps to run a scenario

Step 1:Open the sample scenario in the Editor
Step 2:Select a Display Device and Display Mode
Step 3:Select a Response Button
Step 4:Set the Report Option
Step 5:Run the Scenario
11)What is report header and what are the information contains.
It display general scenario information and it contain the information like (title, scenario, result start time, end time and duration).
Every report has a report header that prints at the beginning of the report.It contains information about report title, a summary table, a chart or any information that only needs to appear once at the reports start.
12)What is scenario wizard .
Through scenario wizard we can create a new scenario.
Scenario wizard is a platform for creating new scenarios.
13)What is smart object recognition
Smart object recognition is used to identify the GUI objects in the screen. When u recording the script automatically the object recogniser records the objects in the screen.
14)What is report viewer .
Each report viewer contain the report header and report viewer tool bar.
Report viewer is a report which contains report viewer tool bar and report header.
15)How to modify the script.
Using vuser script information dialog box.
We can modify script by using vuser scripting information dialog box.
16)What is script list.
It contain all the vuser script that vuser can run.
It is a list which contains the users script which the user can run.
17)During run time where the hosts saves the files.
In temporally in the local drive of each host.
During run time the hosts saves the files temporally in the local drive of each host.
18)What is load runner API function .
Data base vuser do not operate client application .Using load runner API function the database vuser can access the data from the server.
With the help of loadrunner API function the data in the server can be made accessible to the database users.

What is load testing?
Load testing is to test that if the application works fine with the loads that resultfrom large number of simultaneous users, transactions and to determine weather itcan handle peak usage periods.
What is Performance testing?

 Timing for both read and update transactions should be gathered to determine whether system functions are being performed in an acceptable timeframe. Thisshould be done standalone and then in a multi user environment to determine theeffect of multiple transactions on the timing of a single transaction.
Did u use LoadRunner? What version?
Yes.give current version
Explain the Load testing process?
Step 1: Planning the test. Here, we develop a clearly defined test plan to ensure thetest scenarios we develop will accomplish load-testing objectives.
Step 2: Creating Vusers. Here, we create Vuser scripts that contain tasks performedby each Vuser, tasks performed by Vusers as a whole, and tasks measured astransactions.
Step 3: Creating the scenario. A scenario describes the events that occur during atesting session. It includes a list of machines, scripts, and Vusers that run duringthe scenario. We create scenarios using LoadRunner Controller. We can createmanual scenarios as well as goal-oriented scenarios. In manual scenarios, wedefine the number of Vusers, the load generator machines, and percentage of Vusers to be assigned to each script. For web tests, we may create a goal-orientedscenario where we define the goal that our test has to achieve. LoadRunnerautomatically builds a scenario for us.
Step 4: Running the scenario.We emulate load on the server by instructing multiple Vusers to perform taskssimultaneously. Before the testing, we set the scenario configuration andscheduling. We can run the entire scenario, Vuser groups, or individual Vusers.
Step 5: Monitoring the scenario.We monitor scenario execution using the LoadRunner online runtime, transaction,system resource, Web resource, Web server resource, Web application serverresource, database server resource, network delay, streaming media resource,firewall server resource, ERP server resource, and Java performance monitors.
Step 6: Analyzing test results. During scenario execution, LoadRunner records theperformance of the application under different loads. We use LoadRunner’s graphsand reports to analyze the application’s performance.
When do you do load and performance Testing?
We perform load testing once we are done with interface (GUI) testing. Modernsystem architectures are large and complex. Whereas single user testing primarilyon functionality and user interface of a system component, application testingfocuses on performance and reliability of an entire system. For example, a typicalapplication-testing scenario might depict 1000 users logging in simultaneously to asystem. This gives rise to issues such as what is the response time of the system,

does it crash, will it go with different software applications and platforms, can ithold so many hundreds and thousands of users, etc. This is when we set do loadand performance testing.
What are the components of LoadRunner?
 The components of LoadRunner are The Virtual User Generator, Controller, and theAgent process, LoadRunner Analysis and Monitoring, LoadRunner Books Online.
What Component of LoadRunner would you use to record a Script?
 The Virtual User Generator (VuGen) component is used to record a script. Itenables you to develop Vuser scripts for a variety of application types andcommunication protocols.
What Component of LoadRunner would you use to play Back the script inmulti user mode?
 The Controller component is used to playback the script in multi-user mode. This isdone during a scenario run where a vuser script is executed by a number of vusersin a group.
What is a rendezvous point?
You insert rendezvous points into Vuser scripts to emulate heavy user load on theserver. Rendezvous points instruct Vusers to wait during test execution for multipleVusers to arrive at a certain point, in order that they may simultaneously perform atask. For example, to emulate peak load on the bank server, you can insert arendezvous point instructing 100 Vusers to deposit cash into their accounts at thesame time.
What is a scenario?
A scenario defines the events that occur during each testing session. For example, ascenario defines and controls the number of users to emulate, the actions to beperformed, and the machines on which the virtual users run their emulations.
Explain the recording mode for web Vuser script?
We use VuGen to develop a Vuser script by recording a user performing typicalbusiness processes on a client application. VuGen creates the script by recordingthe activity between the client and the server. For example, in web basedapplications, VuGen monitors the client end of the database and traces all therequests sent to, and received from, the database server. We use VuGen to: Monitorthe communication between the application and the server; Generate the requiredfunction calls; and Insert the generated function calls into a Vuser script.
Why do you create parameters?
Parameters are like script variables. They are used to vary input to the server andto emulate real users. Different sets of data are sent to the server each time thescript is run. Better simulate the usage model for more accurate testing from theController; one script can emulate many different users on the system.
What is correlation? Explain the difference between automatic correlationand manual correlation?
Correlation is used to obtain data which are unique for each run of the script and which are generated by nested queries. Correlation provides the value to avoiderrors arising out of duplicate values and also optimizing the code (to avoid nestedqueries). Automatic correlation is where we set some rules for correlation. It can beapplication server specific. Here values are replaced by data which are created bythese rules. In manual correlation, the value we want to correlate is scanned andcreate correlation is used to correlate.
How do you find out where correlation is required? Give few examples fromyour projects?
 Two ways: First we can scan for correlations, and see the list of values which canbe correlated. From this we can pick a value to be correlated. Secondly, we canrecord two scripts and compare them. We can look up the difference file to see forthe values which needed to be correlated. In my project, there was a unique iddeveloped for each customer, it was nothing but Insurance Number, it wasgenerated automatically and it was sequential and this value was unique. I had tocorrelate this value, in order to avoid errors while running my script. I did usingscan for correlation.
Where do you set automatic correlation options?
Automatic correlation from web point of view can be set in recording options andcorrelation tab. Here we can enable correlation for the entire script and chooseeither issue online messages or offline actions, where we can define rules for thatcorrelation. Automatic correlation for database can be done using show output window and scan for correlation and picking the correlate query tab and choose which query value we want to correlate. If we know the specific value to becorrelated, we just do create correlation for the value and specify how the value tobe created.
What is a function to capture dynamic values in the web Vuserscript?
Web_reg_save_param function saves dynamic data information to aparameter.
When do you disable log in Virtual User Generator, When do you choosestandard and extended logs?
Once we debug our script and verify that it is functional, we can enable logging forerrors only. When we add a script to a scenario, logging is automatically disabled.Standard Log Option: When you selectStandard log, it creates a standard log of functions and messages sent during scriptexecution to use for debugging. Disable this option for large load testing scenarios.When you copy a script to a scenario, logging is automatically disabled ExtendedLog Option: Selectextended log to create an extended log, including warnings and other messages.Disable this option for large load testing scenarios. When you copy a script to ascenario, logging is automatically disabled. We can specify which additionalinformation should be added to the extended log using the Extended log options.
How do you debug a LoadRunner script?
VuGen contains two options to help debug Vuser scripts-the Run Step by Stepcommand and breakpoints. The Debug settings in the Options dialog box allow usto determine the extent of the trace to be performed during scenario execution. Thedebug information is written to the Output window. We can manually set the

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