profiler 5.0 help
User threads and system threads
The Threads graph in the Profiler window shows the total number of threads in the profiled application JVM. The tooltip over the graph separates the number into "user" and "system" threads.
The HotSpot JVM runs a number of internal Java threads for its own needs, so the number of threads of your application and the total number of Java threads in the target JVM are different.
If the application is started from the Profiler, the threads are denoted thusly:
- system threads
the number of Java threads active before the application started
- user threads
calculated as the total number of Java threads in the JVM minus the number of system threads
If attached on the fly [see attaching Profiler ] Profiler cannot distinguish between user and system threads, and simply reports the total number of Java threads in the JVM.
See also
