private void processKey(Object row,
      ObjectInspector rowInspector) throws HiveException {
    if (hashAggr) {
      newKeys.setHashKey();
      processHashAggr(row, rowInspector, newKeys);
    } else {
      processAggr(row, rowInspector, newKeys);
    }

    if (countAfterReport != 0 && (countAfterReport % heartbeatInterval) == 0
      && (reporter != null)) {
      reporter.progress();
      countAfterReport = 0;
    }
  }
@return the size of each row
ql/src/java/org/apache/hadoop/hive/ql/exec/GroupByOperator.java