1.Difference Between Functional Testing and Performance Testing

Online Customers prefer to shopping with the Applications which have good functionality and Response time, So to success in online business the Performance of the Web Applications should be good otherwise customers will simply switch to Competitor Sites

1.Difference between Functional testing and Performance Testing

Functionality Testing:

Do business processes function properly after implementation or not

Load Testing:

Will the Application handle the Expected Load?
Does the Application respond quickly enough for the user?
Do business processes function properly under heavy load?

2. When Load Testing comes into picture

3. Why Load Test your Web Application?

Resolving Performance Problems before deployment is more cost efficient
The Failure of Production server due to performance problem is huge loss to the business
Deploy with confidence

4. Disadvantage of Performance testing through Manual Testing

Difficult to maintain resources like test engineers and Client machines
Difficult to synchronize users
Difficult to collect and analyze results
Difficult to achieve test repeatability

5. Advantage of Load Testing Tool

Overcomes resource limitations
Replaces testers with “Virtual Users”
Runs many Vusers on few machines
Controller manages the Vusers
Meaningful results with analysis tools
Repeats tests with scripted actions

6.Terminology & Concepts in Performance Testing

Think Time: Is the idle time of user with the web application between one request and next request.

Request 1Request 2

( user id & Pwd And Click on Sign in)

Think Time

Load Generator Machine: It is a computer used to send requests remotely, also called as Host machine or Load Driving machine.

Load distribution among load generators is useful to generate heavy load.
Remote command launcher enables the controller to start the application on the Host machine. ---RCL is whatever local request can be converted into remote request.
Agent is interface between host machine and controller.

Console Machine: It is a computer, which controls and manages the load test.

Vusers: Vusers emulate the actions of human users working with your applications. A scenario can contain tens, hundreds or even thousands of Vusers

Vuser Script : Recorded script that, when played back, emulate a real user performing the actions.

Business Process: A set of user actions performed in an application to accomplish a business task. Often referred to as a “transaction.”

Response Time:Interval between user’s request and the system response

User’s RequestSystem Response

Response Time

Performance Test Approach

Evaluate System:

The major activities of this phase are

Application walk through
Access to the application
Gathering all requirements
Identify the Performance Goals
Identify the Performance Testing Completion Criteria
Software and Hardware Specifications of the production server

Develop System Assets:

The major activities of this phase are
Designing Test Scripts
Recording test scripts
Preparing test strategy document

Execute Tests:

The major activities of this phase are

Test environment setup
Application setup
Test Data creation
Test Execution
Deriving the execution results and monitoring transaction flow.

Analysis and Validation:

The major activities of this phase are

Analyzing thr Application server and database server resources.

Eg: CPU Usage, Memory Usage.

Analyzing Client side metrics

Eg: Response Time.

Identifying bottlenecks

Terminology

Performance tuning: It is the activity of improving the performance of a Server (By Developers) .

Modifying a system to handle a higher load is performance tuning.

Bottleneck:Identify the part of the system that is degrading the performance.

Simply we can say the resource with highest utilization

Eg : Bottle neck in CPU, Bottleneck in Memory

Smoke Test: Perform trial runs before you jump into test execution.

Note: Run the Test for 10 Virtual users to Confirm the scripting is working and all the environment set up is working

Components of load Runner:

Virtual User Generator ( VUGen) : Captures end-user Business process and Creates automated Performance testing script also know as Virtual User Development environment

LoadRunner Controller: Generates load and collects test results

LoadRunner Analysis: Compiles and displays test results with graphical format

Virtual User Generator

Navigation: Start-Programs- Mercury Load Runner- Virtual user generator

Recording:

Load runner supports 40 types of Applications (HTTP, SAP, CRM, FTP Protocols) .Our discussion limited only to HTTP Protocol.

Navigation: Vugen-File Menu- New-Web(HTTP/HTML)-Click on OK

-VUser Menu –Start Recording-Enter URL-Click on ok- Perform Actions

(Business Process)-Vuser menu –Click on Stop Recording (or Click Square black color button to stop recording).

Note: There are two Views of requests in the Vugen

Script View
Tree View (Recommended)

How Vugen working:

VuGen Captures HTTP To Create a Vuser
Replicates outgoing HTTP
Passes incoming HTML to browser

Toolbar:

Record Toolbar / Run Toolbar / Tree view toolbar
1.Start,End LoadRunner
Transaction
2. Insert Rendezvous
3. Insert Comment
4.Start, Pause, Stop Recording
5. Select Action File
6. New Action File
7.Recording Options / 1. Run
2.Pause Run
3. Stop Run
4.Break Point
5. RunTime Settings
6.Visual Log
7. Launch Scenario /

Step Properties
Insert step After
Insert step Before
Delete step

Action Files

Definition: A recorded business process that, when played back, emulates a real user performing the business process actions on a system.

By default three Action files in the Vugen.

Vuser_init
Action
Vuser_end

Recording in Action1 File:

Invoke Vugen-Click Start recording-Enter URL of site under test –Select Action in the list box-Conduct business process – And click Stop recording.

Virtual User Playback Model

Renaming a Step In the Icon Tree

Select a step to rename
Right-Click Step Icon
Select properties from pop-up Menu
Click General tab of Submit Form Step Properties dialog
Overwrite default name with a descriptive name and click OK

General Options: Vugen-Tools-General Options-Display

Check show browser during replay

Run-time Settings: Vugen-Vuser-RunTime Settings ( Will be covered in later classes)

Transactions

Transactions are useful to measure the performance of Individual or group of requests.
Measure high business risk transactions
Allows performance comparison between different load tests
Helps to identify performance problems

Navigation:

Vugen-Insert-Start Transactions/End Transaction

Use Record Toolbar to insert Transactions

Add Load Transasctions during Recording .

Click Start Recording
Insert Start Transaction
Complete the User Actions
Insert End Transaction

Note1:Choose Transaction Status as “LR_AUTO” when you want LoadRunner to detect the transaction status automatically

Note2: Choose Transaction Status as “LR_PASS / LR_FAIL when you want to set the transaction status manually in the code

-Test Engineer Can Insert Transactions after Recording

Automatic Transactions:

Enable Automatic Transactions in the Run-Time Settings dialog box, General tab.

Vugen-Vuser-RunTime Settings-General tab.

Check

Define each Action as transaction
Define each Step as Transaction

Parameterization

The practice of replacing a recorded value in a Vuser with a placeholder which can represent an expandable range of values.

The Objectives of Parameterization

Solve Date constraints that may occur during playback

Eg: When Second Virtual User accessing the Application user may fail because of the 2/14/99 was yesterday!]

Solve data caching that may occur during playback

Eg: When Second Virtual User accessing the Application, user will get data

from Cache

Solve unique constraints that may occur during playback

Eg: Order number 1234 is already here

Solve data dependency that may occur during playback
Emulate real user activity
Exercise the server

How to parameterize fields using VuGen

Identify field to parameterize (Planning Specification)
Right-click step which contains the field
Select “Properties”
Click Parameter button next to the recorded value
Enter a parameter name (or select from the list)
Confirm that parameter type is "File"
Click the Properties button
Click the Create button and confirm new file creation
Click the Edit button to open the data file in Windows Notepad
Enter new data in the Notepad window
Press Enter after typing each data item (including the last item)
Close Notepad and save the changes

Note: Multiple columns for different parameters are allowed in the same data file

Note2:Select the Data Access Method Sequential

Note3: For the Sequential access method, Iteration Count should equal the number of rows in the data file.

Day6

CHECKPOINTS

The Business Process Works for One User, But May Not Work for Many Concurrent Users.

Functional Testing Under Load: Confirming that all business processes

complete properly while the server(s) handle concurrent usage.

There are Two Types of Checkpoints in the Vugen

Image Check Point
Text Check Point

Creating an Image Check:

In the browser, right click on image to be checked
Select “Save Picture As…” from pop-up menu
Copy existing file name using Ctrl + C
Click Cancel
Right Click on the Requst and Select Insert After
The Add Step dialog opens
SelectImage Check, and click OK.
Check the Image server file name (SRC attribute) check box
Paste the file name into the edit box using Ctrl + V

Creating an Image Check:

Right Click on the Requst and Select Insert After
The Add Step dialog opens
SelectText Check, and click OK.
Enter Expected Value In Search Text box and Click ok.

Note:Enable Checks in Run-Time Settings .

Vuser- Run-Time Settings – Preferences –Enable Image and Text Check-Click on Ok

Note2: •LoadRunner compares a stored, expected value to an actual value obtained during the run

LoadRunner interview questions
1.What is load testing? - Load testing is to test that if the application works fine with the loads that result from large number of simultaneous users, transactions and to determine weather it can handle peak usage periods.
2.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. This should be done standalone and then in a multi user environment to determine the effect of multiple transactions on the timing of a single transaction.
3.Did u use LoadRunner? What version? - Yes. Version 7.2.
4.Explain the Load testing process? -
Step 1: Planning the test. Here, we develop a clearly defined test plan to ensure the test scenarios we develop will accomplish load-testing objectives.
Step 2: Creating Vusers. Here, we create Vuser scripts that contain tasks performed by each Vuser, tasks performed by Vusers as a whole, and tasks measured as transactions.
Step 3: Creating the scenario. A scenario describes the events that occur during a testing session. It includes a list of machines, scripts, and Vusers that run during the scenario. We create scenarios using LoadRunner Controller. We can create manual scenarios as well as goal-oriented scenarios. In manual scenarios, we define 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-oriented scenario where we define the goal that our test has to achieve. LoadRunner automatically builds a scenario for us.
Step 4: Running the scenario. We emulate load on the server by instructing multiple Vusers to perform tasks simultaneously. Before the testing, we set the scenario configuration and scheduling. 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 server resource, 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 the performance of the application under different loads. We use LoadRunner.s graphs and reports to analyze the application.s performance.
5.When do you do load and performance Testing? - We perform load testing once we are done with interface (GUI) testing. Modern system architectures are large and complex. Whereas single user testing primarily on functionality and user interface of a system component, application testing focuses on performance and reliability of an entire system. For example, a typical application-testing scenario might depict 1000 users logging in simultaneously to a system. 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 it hold so many hundreds and thousands of users, etc. This is when we set do load and performance testing.
6.What are the components of LoadRunner? -
The components of LoadRunner are The Virtual User Generator, Controller, and the Agent process, LoadRunner Analysis and Monitoring, LoadRunner Books Online.
7.What Component of LoadRunner would you use to record a Script? - The Virtual User Generator (VuGen) component is used to record a script. It enables you to develop Vuser scripts for a variety of application types and communication protocols.
8.What Component of LoadRunner would you use to play Back the script in multi user mode? -
The Controller component is used to playback the script in multi-user mode. This is done during a scenario run where a vuser script is executed by a number of vusers in a group.
9.What is a rendezvous point? -
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, in order 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.
10. What is a scenario? -
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 to be performed, and the machines on which the virtual users run their emulations.
11.Explain the recording mode for web Vuser script? -
We use VuGen to develop a Vuser script by recording a user performing typical business processes on a client application. VuGen creates the script by recording the activity between the client and the server. For example, in web based applications, VuGen monitors the client end of the database and traces all the requests sent to, and received from, the database server. We use VuGen to: Monitor the communication between the application and the server; Generate the required function calls; and Insert the generated function calls into a Vuser script.
12.Why do you create parameters? -
Parameters are like script variables. They are used to vary input to the server and to emulate real users. Different sets of data are sent to the server each time the script is run. Better simulate the usage model for more accurate testing from the Controller; one script can emulate many different users on the system.
13.What is correlation? Explain the difference between automatic correlation and 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 avoid errors arising out of duplicate values and also optimizing the code (to avoid nested queries). Automatic correlation is where we set some rules for correlation. It can be application server specific. Here values are replaced by data which are created by these rules. In manual correlation, the value we want to correlate is scanned and create correlation is used to correlate.
14.How do you find out where correlation is required? Give few examples from your projects? -
Two ways: First we can scan for correlations, and see the list of values which can be correlated. From this we can pick a value to be correlated. Secondly, we can record two scripts and compare them. We can look up the difference file to see for the values which needed to be correlated. In my project, there was a unique id developed for each customer, it was nothing but Insurance Number, it was generated automatically and it was sequential and this value was unique. I had to correlate this value, in order to avoid errors while running my script. I did using scan for correlation.
15.Where do you set automatic correlation options? -
Automatic correlation from web point of view can be set in recording options and correlation tab. Here we can enable correlation for the entire script and choose either issue online messages or offline actions, where we can define rules for that correlation. 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 be correlated, we just do create correlation for the value and specify how the value to be created.