CountEvents Performance Optimization Project

Overview

This project demonstrates the process of identifying and resolving performance bottlenecks in a Java application. We take a simple event counting program and optimize it for better performance while adhering to 12-factor app principles.

Objectives

• Identify common performance bottlenecks in Java code
• Apply profiling techniques to pinpoint issues
• Implement optimization strategies to improve application speed
• Demonstrate adherence to 12-factor app methodology

Repository Contents

• src/main/java/EventCounter.java: Original version of the application
• src/main/java/OptimizedCountEvents.java: Optimized version of the application
• profiling_results/: Directory containing profiling data and analysis
• docs/performance_report.pdf: Detailed report on optimization process and results

Getting Started

Prerequisites

• Java Development Kit (JDK) 11 or higher
• VisualVM (for profiling)

Running the Application

1. Compile the Java files:

   javac src/main/java/*.java
   

2. Run the original version:

   java -cp src/main/java CountEvents
   

3. Run the optimized version:

   java -cp src/main/java OptimizedCountEvents
   

Profiling

To profile the application using VisualVM:

1. Start VisualVM
2. Run the application with the following command:

   java -Dcom.sun.management.jmxremote -cp src/main/java CountEvents
   

3. In VisualVM, select the running CountEvents application
4. Use the CPU and Memory profiler to analyze performance

Optimization Process

1. Identify Bottlenecks: Used VisualVM to profile CPU and memory usage
2. Code Analysis: Reviewed code for potential improvements
3. Implement Optimizations:
   • Removed unnecessary file I/O operations
   • Optimized memory usage by replacing large arrays with running sums
   • Improved time calculations
   • Enhanced event tracking logic
4. Verify Improvements: Re-profiled the optimized code to confirm performance gains

Key Findings

• Significant reduction in CPU usage
• Decreased memory allocation
• Improved overall execution time
• Better adherence to 12-factor app principles

12-Factor App Compliance

This project demonstrates several 12-factor app principles:

• Config: Use of environment variables for configuration
• Processes: Stateless and share-nothing architecture
• Disposability: Fast startup and graceful shutdown
• Logs: Output to stdout instead of log files

Further Improvements

• Implement dependency management (e.g., Maven or Gradle)
• Set up CI/CD pipeline for automated testing and deployment
• Containerize the application for better dev/prod parity

Contributing

I welcome contributions! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE.md file for details.