JVM Monitoring

• Summary
  • Uptime: Total amount of time since the Java VM was started.
  • Process CPU Time: Total amount of CPU time that the Java VM has consumed since it was started.
  • Total Compile Time: Total accumulated time spent in JIT compilation. The Java VM determines when JIT compilation occurs. The Hotspot VM uses adaptive compilation, in which the VM launches an application using a standard interpreter, but then analyzes the code as it runs to detect performance bottlenecks, or "hot spots".
• Threads
  • Live threads: Current number of live daemon threads plus non-daemon threads.
  • Peak: Highest number of live threads since Java VM started.
  • Daemon threads: Current number of live daemon threads.
  • Total threads started: Total number of threads started since Java VM started, including daemon, non-daemon, and terminated threads.
• Classes
  • Current classes loaded: Number of classes currently loaded into memory.
  • Total classes loaded: Total number of classes loaded into memory since the Java VM started, including those that have subsequently been unloaded.
  • Total classes unloaded: Number of classes unloaded from memory since the Java VM started.
• Memory
  • Current heap size: Number of kilobytes currently occupied by the heap.
  • Committed memory: Total amount of memory allocated for use by the heap.
  • Maximum heap size: Maximum number of kilobytes occupied by the heap.
  • Objects pending for finalization: Number of objects pending for finalization.
  • Garbage collector: Information about garbage collection, including the garbage collector names, number of collections performed, and total time spent performing GC.
• Operating System
  • Total physical memory: Amount of random-access memory (RAM) the operating system has.
  • Free physical memory: Amount of free RAM available to the operating system.
  • Committed virtual memory: Amount of virtual memory guaranteed to be available to the running process.
• Other Information
  • VM arguments: The input arguments the application passed to the Java VM, not including the arguments to the main method.
  • Class path: The class path that is used by the system class loader to search for class files.
  • Library path: The list of paths to search when loading libraries.
  • Boot class path: The boot class path is used by the bootstrap class loader to search for class files.