Saturday, April 27, 2024

Understanding the `vufd` Option in LoadRunner Enterprise (LRE) | LoadRunner vufd

What Is the `vufd` Option?

The `vufd` option, short for Virtual User Functional Data, is a set of parameters and settings in LoadRunner Enterprise that allows users to control how virtual users interact with an application during performance tests. Virtual users (VUs) simulate real users, and the `vufd` option helps manage their functional data, which includes the input and output data for these simulated users.

 Importance of `vufd` in Performance Testing:

1. Realistic User Simulation: By managing the functional data for virtual users, the `vufd` option helps simulate realistic user interactions with an application. This provides a more accurate representation of how the application will perform in real-world scenarios.

2. Test Data Management: Proper management of test data is crucial for accurate performance testing. The `vufd` option allows users to control the data used by virtual users, ensuring consistency and reliability in test results.

3. Enhanced Analysis: With the `vufd` option, testers can collect and analyze data from virtual users more effectively. This data can provide insights into application performance, identify bottlenecks, and guide optimization efforts.

How to Leverage the `vufd` Option:

1. Configure Virtual Users: Start by setting up virtual users with realistic profiles and behaviors. Use the `vufd` option to manage the functional data these users interact with during testing.

2. Use Parameterization: Parameterize the virtual user scripts to simulate different user scenarios and inputs. This allows you to test a variety of use cases and better understand application performance.

3. Monitor Performance: During testing, closely monitor the performance of the application as virtual users interact with it. Look for patterns in the data collected using the `vufd` option.

4. Analyze Results: After the test, analyze the data collected from virtual users. Identify any issues with application performance and use the insights to optimize the application for better user experiences.

5. Iterate and Improve: Based on the analysis, make improvements to the application and the test scripts. Repeat the process to continue refining performance and ensuring a high-quality user experience.

The `vufd` option in LoadRunner Enterprise is a key feature that enables testers to manage Virtual User Functional Data effectively. By leveraging this option, you can create realistic user simulations, manage test data, and gain valuable insights into application performance. Whether you are testing a web application, a mobile app, or an API, the `vufd` option can help you ensure your application performs optimally under varying levels of load.

How to Save the downloaded file to local system in load runner

In certain scenarios, downloading files becomes a requirement. Instead of needing to store the files on your local machine for later verification, you may want to measure the transaction time of the download process. To do this, you can capture data from the server response and save it to a file using standard file operations. Just be sure you know the type of file you will be downloading.

Here's an example of downloading a `.pdf` file and saving it to your local system:


// Declare variables
int filePointer;
long fileSize;

// Create a file for writing
filePointer = fopen("c://test_file.pdf", "wb");

// Start a transaction to measure download time
lr_start_transaction("file_download");

// Increase the parameter size to accommodate the data
web_set_max_html_param_len("100000");

// Use web_reg_save_param with the appropriate boundaries to capture server response data for the download
web_reg_save_param("FILEDATA", "LB=", "RB=", "Search=Body", LAST);

// HTTP request to download the .pdf file
web_url("http://serverURL:port/app/resource/getme.pdf");

// Retrieve the download size
fileSize = web_get_int_property(HTTP_INFO_DOWNLOAD_SIZE);

// Write the captured data to an output file
fwrite(lr_eval_string("{FILEDATA}"), fileSize, 1, filePointer);

// End the transaction
lr_end_transaction("file_download", LR_AUTO);

// Close the file
fclose(filePointer);

This code snippet demonstrates how to use file operations and LoadRunner functions to download a PDF file from a server, capture the download data, save it to a local file, and measure the transaction time. By following this process, you can efficiently analyze the download performance without needing to store the downloaded files on your machine for later verification.

Python Script for Dynamically Generating LoadRunner Transaction Names | Automate Transaction Names in LoadRunner

In performance testing and monitoring, it's crucial to understand how different parts of your application are performing under various conditions. Monitoring transactions around key sections of code, such as API calls and critical functions, helps identify performance bottlenecks and areas for optimization. LoadRunner provides powerful tools for performance testing, including functions like `lr_start_transaction` and `lr_end_transaction` that enable you to measure the execution time of specific code blocks. However, adding these functions manually can be a time-consuming and error-prone process. To streamline this task, I've developed a script that automatically inserts transaction monitoring statements around key function calls in a C file. This script simplifies the process and helps you achieve more efficient and consistent performance testing results. Let's explore how this script works.

import re

# Open the data file
with open('C:\\Users\\easyloadrunner\\Downloads\\FeatureChange-V1\\Action.c', 'r') as file:
    data = file.read()

# Split the data into lines
lines = data.split('\n')

# Initialize a variable to store the captured value
captured_value = ""

# Open the output file
with open('C:\\Users\\easyloadrunner\\Downloads\\FeatureChange-V1\\ModifiedAction.C', 'w') as output_file:
    # Loop through each line
    for line in lines:
        # Check if the line contains "web_custom_request "
        if "web_custom_request(" in line:
            # Use regular expression to capture the dynamic value
            captured_value = re.search(r'web_custom_request\("(.+?)"', line).group(1)
            # Add the captured value to the start of the transaction
            new_line = 'lr_start_transaction("' + captured_value + '");\n' + line
        elif "LAST);" in line:
            # Add the end of the transaction
            new_line = line + '\n' + 'lr_end_transaction("' + captured_value + '", LR_AUTO);'
        else:
            new_line = line
        # Write the modified line to the output file
        output_file.write(new_line + '\n')

BatchJob Performance Testing | Batch Job Performance Testing with JMeter

Batch job performance testing involves evaluating the efficiency, scalability, and reliability of batch processes. Start by setting clear goals and objectives for the testing, such as response times and throughput rates. Identify key batch jobs for testing based on business impact and usage patterns. Design test scenarios reflecting normal, peak, and edge cases, and prepare test data sets that resemble production data.

Automate test execution using tools like Apache JMeter and configure the tests to run batch jobs using appropriate samplers. Monitor key performance metrics such as response times, CPU and memory usage, and disk I/O. Conduct load and stress tests to evaluate performance under various conditions, identifying bottlenecks and areas for improvement.

Analyze test results, optimize batch jobs as needed, and re-test to verify improvements. Document findings and recommendations for stakeholders, and incorporate regular performance testing as part of continuous improvement to maintain efficient batch job performance.Batch jobs are automated tasks that run without direct user involvement. They are vital in many sectors for operations such as data backup, processing, report creation, system upkeep, file management, automated testing, database administration, financial transactions, job scheduling, and data archiving.

Types of Batch Jobs:

1. Data Backup and Recovery Jobs: These tasks involve regularly backing up crucial data and databases to ensure data safety and restore points in case of data loss. For instance, a job might back up a company's customer data every night.

2. Data Processing and ETL Jobs: These jobs are used for data extraction, transformation, and loading tasks in data warehousing scenarios. For example, a job may extract data from various sources, transform it to a standard format, and load it into a data warehouse.

3. Report Generation Jobs: These generate complex reports during off-peak hours to minimize impact on system performance. For instance, a job might generate monthly sales reports for management overnight.

4. System Maintenance Jobs: These handle routine maintenance tasks like clearing temporary files and rotating log files. For example, a job might clean up old log files and free up disk space weekly.

5. File Processing Jobs: These tasks manage large file volumes, such as converting file formats and validating data. For instance, a job might convert image files from one format to another and validate data consistency.

6. Automated Testing Jobs: These run tests on applications automatically, ensuring they work as expected without constant user input. For example, a job might perform end-to-end tests on a web application every night.

7. Database Maintenance Jobs: These perform tasks like reindexing databases and checking data integrity. For instance, a job might run a routine maintenance check on a database to ensure optimal performance.

8. Batch Processing in Financial Systems: These jobs handle financial tasks such as payroll processing or generating financial reports. For example, a job might process employee payroll data and generate paychecks every two weeks.

9. Job Scheduling and Automation: These automate various tasks at specific times or intervals. For example, a job might automatically generate backups every evening at 11 p.m.

10. Data Archiving Jobs: These handle archiving old data to maintain optimal database performance and storage usage. For instance, a job might archive data older than five years to a secondary storage location.

Creating a Basic Batch Job using JMeter:

Example: An example of a simple batch job is copying files from one folder to another written in python script. This operation might be scheduled to run every day at midnight, ensuring data consistency and security.

Testing the Batch Job with JMeter:
JMeter can be used to simulate and test the performance of batch jobs. By creating a thread group and adding an OS processor sampler, you can run the batch job command within JMeter. Adding listeners like Aggregate Graph and Summary Report allows you to evaluate performance metrics such as average response time and percentiles.




Metrics for Batch Processing Performance:
  •  Throughput: Number of tasks or commands completed in a specified time period.
  •  Latency: Time taken for a task or command to be submitted and completed.
  •  Utilization: Percentage of available resources (e.g. CPU, memory, disk, network) used during the batch process.
  •  Error Rate: Percentage of tasks or commands that fail or produce incorrect results.
  •  Additional Metrics: May include cost, reliability, scalability, or security, depending on your objectives.
 Data Collection and Analysis:

  • Logging: Record events and messages generated by the batch process in a file or database.
  • Monitoring: Observe and measure performance and status of the batch process and resources used in real time or periodically.
  • Profiling: Identify and measure time and resources consumed by each part or function of the batch process.
  • Auditing: Verify and validate output and results of the batch process against expected standards and criteria.
Use collected data to identify bottlenecks, errors, inefficiencies, or anomalies affecting performance and find root causes and solutions.

Optimizing and Improving Batch Processing Performance:
  • Parallelization: Divide the batch process into smaller, independent tasks or commands to run simultaneously on multiple processors or machines.
  • Scheduling: Determine optimal time and frequency to run the batch process based on demand, availability, priority, or dependency of tasks or commands.
  • Tuning: Adjust parameters, settings, or options of the batch process, resources, or environment to enhance performance and quality.
  •  Testing: Evaluate and compare performance and results before and after applying optimization techniques to ensure they meet expectations and requirements.
   Happy Testing!