public static void main(String[] args) throws IOException {
    MasterProcedureSchedulerPerformanceEvaluation tool =
      new MasterProcedureSchedulerPerformanceEvaluation();
    tool.setConf(UTIL.getConfiguration());
    tool.run(args);
  }
Starts the threads and waits for them to finish.
@return time taken by threads to complete, in milliseconds.
hbase-server/src/test/java/org/apache/hadoop/hbase/master/procedure/MasterProcedureSchedulerPerformanceEvaluation.java