When should you prefer Java Flight Recorder (JFR) and when should you avoid it?

Java Flight Recorder (JFR) is a powerful tool for collecting diagnostic and profiling information about Java applications. However, whether to use JFR depends on the specific requirements and context of your application. Below are some scenarios when to prefer JFR and when to avoid it.

When to Prefer Java Flight Recorder (JFR)

• Performance Monitoring: Use JFR for real-time performance analysis in production environments. It captures low-level details with minimal impact on application performance.
• Profiling: When you need detailed insights on CPU usage, memory management, and I/O operations, JFR provides comprehensive profiling capabilities.
• Event Analysis: If you want to analyze various application events (like garbage collection, thread state changes, etc.), JFR helps in gathering this data effectively.
• Long-Running Applications: For applications that run for extended periods, JFR's ability to record events over time assists in finding performance degradation.

When to Avoid Java Flight Recorder (JFR)

• Memory Overhead: If your application is highly sensitive to memory usage, be cautious with JFR, as it does introduce some overhead.
• Development Phase: In the early stages of development or for quick prototyping, consider simpler profiling tools that might be easier to set up and use.
• Specific Use Cases: If you need specialized metrics or visualizations that JFR doesn't provide, alternative profiling tools might be more suitable.
• Complexity: If your team lacks experience with JFR or if your application does not require in-depth analysis, it might be easier to use less complex monitoring solutions.