@SuppressWarnings("deprecation")
  @Override
  public MapJoinKey putRow(Writable currentKey, Writable currentValue)
      throws SerDeException, HiveException, IOException {
    writeHelper.setKeyValue(currentKey, currentValue);
    return internalPutRow(writeHelper, currentKey, currentValue);
  }
Get the current memory usage by recalculating it.
@return current memory usage
ql/src/java/org/apache/hadoop/hive/ql/exec/persistence/HybridHashTableContainer.java