PMI counters aggregation alghoritm

Question

Hello

The question is regarding logic that is hidden behind word "aggregate" in PMI documentation.

From IBM WebSphere Developer Technical Journal: Writing PMI applications using the JMX interface

" A module can have sub-modules and each module/sub-module will have related performance data (that is, metric or counter). For instance, the Thread Pool module has two sub-modules: Web Container pool and ORB pool. Each of these sub-modules will have performance data, such as pool size, active threads, etc., and the parent Thread Pool module will aggregate the data from the sub-modules. "

I would relay on JSR77 but it also doesn't provide any information about logic how data should be aggregated in hierarchical structure from child to parent.

Simple example:

• ThreadPools
  
  • Module A
    
    • size = 100
      
  • Module B
    
    • size = 1
      
  • size = ? . What size will I get for parent node from PMI?
    

If logic is simple and PMI just calculate average value. Does it used it for all types of counters?

Thanks, Alexander