what does SHOW /*!50000 GLOBAL */ STATUS do ?
The "50000" refers to a MySQL version -- it means that only version 5.0.0 and above should pay attention to that command.  5.0.0+ will see SHOW GLOBAL STATUS, while earlier versions will see just SHOW STATUS.

Example:

mysql&gt; /*!50511 select 1 */;
+---+
| 1 |
+---+
| 1 |
+---+
1 row in set (0.00 sec)

mysql&gt; /*!50512 select 1 */;
Query OK, 0 rows affected (0.00 sec)


(I have MySQL 5.5.11 -- i.e. 5.05.11).