void registerAttemptDirs(AttemptPathIdentifier identifier,
                                    AttemptPathInfo pathInfo) {
      LOG.debug("Registering " + identifier + " via watcher");
      pathCache.put(identifier, pathInfo);
    }
Unregister a specific dag

This method and registerDag must be synchronized externally to prevent races in shuffle token registration/unregistration

@param dir
@param applicationIdString
@param dagIdentifier
llap-server/src/java/org/apache/hadoop/hive/llap/shufflehandler/ShuffleHandler.java