private void copyFiles() throws IOException, LoginException {
    if (mmCtx == null) {
      for (Path dataPath : dataPathList) {
        copyOneDataPath(dataPath, exportRootDataDir);
      }
    } else {
      copyMmPath();
    }
  }
This writes the actual data in the exportRootDataDir from the source.
ql/src/java/org/apache/hadoop/hive/ql/parse/repl/dump/io/FileOperations.java