docs: private static float computeRowUsageFraction(final long numRows, final long train_samples_per_iteration, final boolean replicate_training_data) {
      float rowUsageFraction = (float)train_samples_per_iteration / numRows;
      if (replicate_training_data) rowUsageFraction /= H2O.CLOUD.size();
      assert(rowUsageFraction > 0);
      return rowUsageFraction;
    }