public RestoreMetaChanges restoreHdfsRegions() throws IOException {
    ThreadPoolExecutor exec = SnapshotManifest.createExecutor(conf, "RestoreSnapshot");
    try {
      return restoreHdfsRegions(exec);
    } finally {
      exec.shutdown();
    }
  }
Restore the on-disk table to a specified snapshot state.
@return the set of regions touched by the restore operation
hbase-server/src/main/java/org/apache/hadoop/hbase/snapshot/RestoreSnapshotHelper.java