Strange PBXT issue

MariaDB [test]> create table b (a int primary key) engine=pbxt;
Query OK, 0 rows affected (3 min 43.59 sec)


MariaDB [test]> insert into b values(1);
Query OK, 1 row affected (8.08 sec)


MariaDB [test]> insert into b values(2);
Query OK, 1 row affected (8.08 sec)


MariaDB [test]> insert into b values(3);
Query OK, 1 row affected (1 min 21.43 sec)


MariaDB [test]> select * from b;
+---+
| a |
+---+
| 1 |
| 2 |    Hmmm? where is 3?
+---+
2 rows in set (0.00 sec)


MariaDB [test]> insert into b values(3);
ERROR 1062 (23000): Duplicate entry '3' for key 'PRIMARY'


MariaDB [test]> select * from b where a  = 3;
+---+
| a |
+---+
| 3 |
+---+
1 row in set (0.10 sec)


MariaDB [test]> select * from b order by a;
+---+
| a |
+---+
| 1 |
| 2 |
| 3 |
+---+
3 rows in set (0.00 sec)