// ConcurrentHashMap does not need synch. here

        for (Iterator<Map.Entry<JMeterThread, Thread>> iterator = allThreads.entrySet().iterator(); iterator.hasNext();) {

        for (JMeterThread item : allThreads.keySet()) {

            Map.Entry<JMeterThread, Thread> entry = iterator.next();

            item.stop();

            entry.getKey().stop();

            // 51880

            entry.getValue().interrupt();