Top 12 LoadRunner Interview Questions and Answers

LoadRunner Interview Questions and Answers

LoadRunner is the best application performance testing tool out there, which makes it extremely sought-after in the IT world. Despite its powerful capabilities, LoadRunner provides an intuitive user interface and scripting environment, making it accessible to both experienced testers and those new to performance testing. This makes LoadRunner a perfect platform for any IT candidate’s career. That is why, we have curated these LoadRunner Interview Questions and Answers to give you a chance to impress in your LoadRunner interview.

LoadRunner Interview Questions and Answers

1. What is LoadRunner?

LoadRunner, developed by Micro Focus, is a performance testing tool utilized for assessing the performance, reliability, and scalability of applications by replicating real user behavior across diverse load scenarios. Testers leverage LoadRunner to design and execute performance evaluations for a broad spectrum of applications, spanning web, mobile, and enterprise realms.

2. What is Elapsed Time in LoadRunner?

In LoadRunner, “Elapsed Time” denotes the total duration of executing a performance test, encompassing script initialization, ramp-up, steady-state execution, ramp-down, and post-execution tasks like result analysis. It’s vital for evaluating overall application performance, assessing load sustainability, detecting performance issues, and comparing results across different tests. This metric offers insights into system responses to load variations, aiding in performance optimization and scalability improvements.

3. Explain Correlation in LoadRunner.

Correlation in LoadRunner involves dynamically capturing and replacing changing values within scripts, like session IDs or authentication tokens. These values, recorded during script creation, need to be correlated to ensure accurate script replay and realistic load testing. This process entails identifying dynamic values, creating extraction rules, and replacing them with parameterized values in subsequent requests.

4. Describe the types of Correlation in LoadRunner.

The following are the types of Correlations in LoadRunner:

• Manual Correlation: Testers manually spot dynamic values in server responses and craft extraction rules to capture and swap them with parameters. Though it demands manual effort and scripting skills, it provides precise control over correlation.

• Automatic Correlation: LoadRunner’s built-in engine scans server responses during recording, identifying and correlating dynamic values automatically. This streamlines the process, reducing manual intervention and script maintenance time.

• Rule-based Correlation: Testers establish correlation rules according to patterns or structures of dynamic values in server responses. LoadRunner then applies these rules to spot and correlate similar dynamic values during script replay.

• Dynamic Parameterization: Instead of substituting dynamic values with fixed parameters, dynamic parameterization generates unique values dynamically during script execution.

5. What is a scenario in LoadRunner?

In LoadRunner, a scenario is a predefined set of user behaviors simulated during a performance test. It includes key parameters like the number of virtual users, ramp-up and ramp-down periods, and workload distribution.

6. Explain the concept of ramp up and ramp down in LoadRunner.

In LoadRunner, ramp-up and ramp-down denote the gradual increment and decrement, respectively, of virtual user numbers during a performance test scenario.

• Ramp-up: During the ramp-up phase, virtual users are added incrementally to the test scenario over a designated time frame. This gradual addition mimics real-world user load escalation, allowing testers to evaluate application performance under increasing user activity. Ramp-up aids in pinpointing performance bottlenecks, resource limitations, and scalability concerns as the user load grows.

• Ramp-down: Conversely, ramp-down involves the gradual reduction of virtual user numbers towards the end of the test scenario. This gradual decline facilitates a smooth conclusion to the performance test, enabling the application to revert to normal operational conditions gradually. Ramp-down assists in observing application behavior as user load decreases and in identifying any issues related to cleanup or resource management.

7. Explain the steps involved creating a Vuser script.

Creating a Vuser script in LoadRunner involves the following steps:

• Open LoadRunner: Launch LoadRunner and choose the appropriate protocol for recording, such as HTTP/HTML, Web Services, Oracle NCA, or SAP GUI, based on the application you’re testing.

• Initiate Recording: Start the recording session in LoadRunner, configuring settings like the target application URL, recording mode (GUI-based or URL-based), and any additional options.

• Record User Actions: Interact with the target application to perform actions that need to be simulated during the performance test. LoadRunner captures network traffic and generates a script based on these actions.

• Script Enhancement (Optional): After recording, enhance the script by modifying transactions, adding checkpoints for validation, parameterizing dynamic values, correlating session IDs or tokens, and managing dynamic content.

• Validate the Script: Ensure the recorded script accurately reflects the desired user interactions with the application. Check for errors or discrepancies that could affect script replay or test results.

• Save the Script: Save the Vuser script in LoadRunner’s script repository or on your local computer. Use descriptive naming and organize the scripts for future reference.

• Customize Runtime Settings (Optional): Adjust the runtime settings for the Vuser script, such as the number of iterations, duration, load distribution, and any other specific requirements for performance testing.

• Execute the Script: Run the script to simulate user load on the target application. LoadRunner monitors performance metrics like response times, throughput, and resource usage during execution.

• Analyze the Results: After script execution, analyze the test results to assess application performance, identify any issues or bottlenecks, and make informed decisions for optimization.

8. Explain the need for Checkpoints and types of checkpoints available in LoadRunner.

Checkpoints play a vital role in LoadRunner scripts by enabling testers to verify the behavior and functionality of the application during performance testing. They act as checkpoints, ensuring that the application behaves as expected under different load conditions. The need for checkpoints stems from various reasons:

• Validating Responses: Checkpoints validate server responses against anticipated values or conditions, ensuring the application functions correctly and delivers expected outputs under load.

• Error Detection: Checkpoints aid in identifying errors or irregularities in the application’s behavior during performance testing. By comparing actual responses to expected outcomes, testers can pinpoint discrepancies and potential issues requiring attention.

• End-to-End Testing: Checkpoints facilitate end-to-end testing by confirming the accuracy of data flow and transactional integrity across various application components, including web pages, forms, databases, and APIs.

• Enhanced Test Coverage: By strategically placing checkpoints in scripts, testers ensure comprehensive test coverage, validating critical functionalities and user interactions throughout the application.

LoadRunner offers diverse checkpoint types to cater to varying validation needs:

• Text Checkpoint: Verifies the presence, absence, or specific content of text strings within application responses.

• Image Checkpoint: Validates the appearance and attributes of images displayed on web pages, ensuring they align with expected criteria.

• XML Checkpoint: Verifies the structure, content, and values of XML documents returned by the server, ensuring compliance with predefined standards.

• Database Checkpoint: Validates data retrieved from databases by executing SQL queries and comparing results against expected values or conditions.

• Content Checkpoint: Verifies the content and attributes of web elements like links, buttons, forms, and tables, ensuring accurate display and functionality.

• Page Checkpoint: Validates the properties and attributes of web pages, such as titles, URLs, and meta tags, to ensure compliance with predefined criteria.

9. What are the components of LoadRunner?

LoadRunner comprises three primary components:

• Virtual User Generator (VuGen): VuGen facilitates script recording and editing tasks. It enables testers to record user interactions with the application being tested and refine scripts by incorporating parameters, correlation, and other customizations.

• Controller: The Controller serves as the hub for test scenario management and execution. Testers utilize the Controller to define test scenarios, configure load distribution, establish pacing, and monitor test progress in real-time.

• Analysis: Analysis is dedicated to result analysis and reporting functions. It equips users with tools and functionalities to scrutinize performance metrics, pinpoint bottlenecks, and compile comprehensive reports tailored for stakeholders’ understanding.

10. What is parameterization in LoadRunner?

Parameterization in LoadRunner replaces static values in scripts with dynamic parameters to emulate real-world scenarios, varying data across user sessions. This enhances test flexibility, realism, and allows for easier script maintenance without altering logic, ensuring more accurate performance tests.

11. What are the types of performance tests supported by LoadRunner?

LoadRunner accommodates diverse performance tests, comprising:

• Load Testing: Examining system performance under anticipated loads to guarantee it can manage projected user engagement.

• Stress Testing: Assessing system resilience by exceeding its typical operational limits, revealing weak points and potential failure scenarios.

• Endurance Testing: Gauging system performance across prolonged periods under consistent loads to detect resource utilization, memory leaks, or performance decline issues.

• Spike Testing: Analyzing system response to abrupt spikes in user traffic or load, evaluating scalability and adaptability to unforeseen activity surges.

• Volume Testing: Confirming system performance with substantial data volumes to ensure uninterrupted functionality despite data volume increments.

• Scalability Testing: Estimating system scalability with growing loads, ensuring it can accommodate expanding user bases and transaction volumes efficiently.

12. How is user load simulated in LoadRunner?

Simulating user load in LoadRunner involves creating virtual user scripts, setting up test scenarios via the Controller, and executing tests to mimic user activity on the application being tested.

Conclusion

These LoadRunner Interview Questions and Answers are specially curated for our students to use as a reference in getting an overall grasp in LoadRunner, that will give them an understanding of the type of questions that can be expected in the LoadRunner interview. So, we hope that this LoadRunner Interview Questions and Answers serves its purpose rightfully to the students.