code: public static void logPerIteration(long startTimeMs, int times, String msg, int workerId) {
      long takenTimeMs = System.currentTimeMillis() - startTimeMs;
      double result = 1000.0 * sFileBytes / takenTimeMs / 1024 / 1024;
      LOG.info(times + msg + workerId + " : " + result + " Mb/sec. Took " + takenTimeMs + " ms. ");
    }
docs: Writes log information.
  
  @param startTimeMs the start time in milliseconds
  @param times the number of the iteration
  @param msg the message
  @param workerId the id of the worker