code: ThroughputDistribution getThroughputDistribution(int activeThreads, boolean create) {
          if (activeThreads < coreThreads)
              activeThreads = coreThreads;
          Integer threads = Integer.valueOf(activeThreads);
          ThroughputDistribution throughput = threadStats.get(threads);
          if ((throughput == null) && create) {
              throughput = new ThroughputDistribution();
              throughput.setLastUpdate(controllerCycle);
              threadStats.put(threads, throughput);
          }
          return throughput;
      }
docs: Get the throughput distribution data associated with the specified
  number of active threads.
  
  @param activeThreads the number of active threads when the data was
  collected
  
  @param create whether to create and return a new throughput distribution
  if none currently exists
  
  @return the data representing the throughput distribution for the
  specified number of active threads