protected DynamicThread addActiveThread() {
   DynamicThread threadWorker = makeThread(threadIndex++);
   owner.addThread(threadWorker);
   Thread thread = new Thread(threadWorker, threadWorker.getThreadName());
   threadWorker.setOSThread(thread);
   thread.setDaemon(false); // we can't have it daemon, since it will stay and eat RAM in UI mode
   thread.start();
   treeClone = cloneTree(threadGroupTree); // use background time to clone tree
   return threadWorker;
 }
 protected DynamicThread makeThread(long threadIndex) {
   boolean onErrorStopTest = owner.getOnErrorStopTest();
   boolean onErrorStopTestNow = owner.getOnErrorStopTestNow();
   boolean onErrorStopThread = owner.getOnErrorStopThread();
   boolean onErrorStartNextLoop = owner.getOnErrorStartNextLoop();
   final DynamicThread jmeterThread = new DynamicThread(treeClone, this.owner, notifier);
   jmeterThread.setThreadNum((int) threadIndex);
   jmeterThread.setThreadGroup(this.owner);
   jmeterThread.setInitialContext(context);
   final String threadName = owner.getName() + " " + groupIndex + "-" + (threadIndex + 1);
   jmeterThread.setThreadName(threadName);
   jmeterThread.setEngine(engine);
   jmeterThread.setOnErrorStopTest(onErrorStopTest);
   jmeterThread.setOnErrorStopTestNow(onErrorStopTestNow);
   jmeterThread.setOnErrorStopThread(onErrorStopThread);
   jmeterThread.setOnErrorStartNextLoop(onErrorStartNextLoop);
   return jmeterThread;
 }