idleTimeout should be added to close idle connections

[Chen Yangjian]

...to prevent connection squatting. The default max connections in mysql is 100-151:

mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 151   |
+-----------------+-------+
1 row in set (0.03 sec)

• https://stackoverflow.com/questions/22297773/how-to-increase-mysql-connectionsmax-connections