@VisibleForTesting
  void initSavePath() {
    if (savePath == null) {
      String dir = HiveConf.getVar(conf, ConfVars.LLAP_CACHE_HYDRATION_SAVE_DIR);
      String name = RegistryUtilities.getCanonicalHostName();
      if (dir != null && name != null) {
        createDirIfNotExists(dir);
        savePath = dir + Path.SEPARATOR + name.hashCode() + ".cache";
      }
    }
  }
Simple cache hydration strategy which saves the content info of the cache to a file on the local filesystem on
shutdown, and loads it when the daemon starts.
llap-server/src/java/org/apache/hadoop/hive/llap/cache/BasicLlapCacheHydration.java