Wordfence producing large amounts of GRA logs in Galera DB Cluster

Hi, we have recently moved our wordpress instance to use percona xtradb cluster as the MySQL backend for HA purpose.

We have noticed that wordfence produces a significant number of GRA logs in the backup nodes of DB cluster.

For information on GRA logs of DB cluster, you may refer to the following page:
https://www.percona.com/blog/2012/12/19/percona-xtradb-cluster-pxc-what-about-gra_-log-files/

basically GRA logs are DB queries that failed to populate to the peer nodes in the DB cluster.

Posted here is a GRA log caused by wordfence query:

/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!40019 SET @@session.max_insert_delayed_threads=0*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at 4
#120715 3:45:56 server id 1 end_log_pos 107 Start: binlog v 4, server v 5.5.25-debug-log created 120715 3:45:56 at startup
# Warning: this binlog is either in use or was not closed properly.
ROLLBACK/*!*/;
BINLOG ‘
NHUCUA8BAAAAZwAAAGsAAAABAAQANS41LjI1LWRlYnVnLWxvZwAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAA0dQJQEzgNAAgAEgAEBAQEEgAAVAAEGggAAAAICAgCAA==
‘/*!*/;
# at 107
#160722 9:24:53 server id 1 end_log_pos 105 Query thread_id=26751 exec_time=0 error_code=0
use wp_database/*!*/;
SET TIMESTAMP=1469193893/*!*/;
SET @@session.pseudo_thread_id=26751/*!*/;
SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/*!*/;
SET @@session.sql_mode=1073741824/*!*/;
SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/;
/*!\C utf8mb4 *//*!*/;
SET @@session.character_set_client=45,@@session.collation_connection=45,@@session.collation_server=8/*!*/;
SET @@session.lc_time_names=0/*!*/;
SET @@session.collation_database=DEFAULT/*!*/;
UPDATE wp_wfConfig SET val=? WHERE name=?
/*!*/;
DELIMITER ;
# End of log file
ROLLBACK /* added by mysqlbinlog */;
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/;

Does anybody have any insight on how to address this problem?

Thanks,
Leo

https://wordpress.org/plugins/wordfence/