@Override public List<String> getAllTables(String catName, String dbName) throws MetaException {
    return rawStore.getAllTables(catName, dbName);
  }
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