When should you prefer jcmd and when should you avoid it?

The jcmd command is a powerful tool for managing Java applications and can be used for various tasks such as monitoring, debugging, and performing diagnostics. However, there are specific scenarios where it is more beneficial to use jcmd as well as situations where it might not be the best choice.

When to Prefer jcmd

• Real-time Monitoring: If you need real-time data about your JVM and applications, jcmd provides insights into memory usage, CPU usage, thread states, etc.
• Diagnostics: It is very useful for diagnosing performance issues, collecting garbage collection statistics, or getting thread dumps.
• Interactivity: Use jcmd for interactive management capabilities, such as sending commands to a running JVM.
• Post-mortem Analysis: You can use jcmd to analyze core dumps or heap dumps generated by the JVM.

When to Avoid jcmd

• Non-JVM Applications: If you're working with applications not running on the JVM, jcmd will not apply.
• Automation: For automating tasks in production systems where minimal risk and stability are crucial, consider alternatives that may provide safer options.
• Performance Overhead: Frequent commands and heavy tools can incur an overhead, so avoid using jcmd in performance-critical applications without careful measurement.
• Security Concerns: If your application operates in high-security environments, be cautious about exposing jcmd capabilities that could potentially be exploited.

Example

    jcmd  GC.heap_dump