code: public static synchronized void init() {
          if (initialized)
              return;
          if (tc.isEntryEnabled()) {
              Tr.entry(tc, "init");
          }
  
          initialized = true;
          //defaultLevel = StatConstants.STATISTIC_SET_EXTENDED;
          defaultLevel = StatConstants.STATISTIC_SET_BASIC;
          moduleRoot = new ModuleItem();
          setInstrumentationLevel(defaultLevel);
          //disabled = false;
          try {
              MBeanServer mServer = ManagementFactory.getPlatformMBeanServer();
              ObjectName pmiMBean = new ObjectName(PmiConstants.MBEAN_NAME);
              mServer.registerMBean(PmiCollaboratorFactory.getPmiCollaborator(), pmiMBean);
              printAllMBeans();
          } catch (Exception e) {
              Tr.error(tc, "Unable to create Perf MBean.");
              FFDCFilter.processException(e, "com.ibm.ws.pmi.server.PmiRegistry", "Init");
          }
          if (tc.isEntryEnabled()) {
              Tr.exit(tc, "init");
          }
      }
docs: Initialize: module configs, module aggregates