@Override public List<TableMeta> getTableMeta(String catName, String dbNames, String tableNames,
      List<String> tableTypes) throws MetaException {
    return rawStore.getTableMeta(catName, dbNames, tableNames, tableTypes);
  }
This starts a background thread, which initially populates the SharedCache and later
periodically gets updates from the metastore db

@param conf
@param runOnlyOnce
@param shouldRunPrewarm
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/cache/CachedStore.java