ConnectionPoolConfiguration - Amazon Relational Database Service


Specifies the settings that control the size and behavior of the connection pool associated with a DBProxyTargetGroup.



In the following list, the required parameters are described first.


The number of seconds for a proxy to wait for a connection to become available in the connection pool. This setting only applies when the proxy has opened its maximum number of connections and all connections are busy with client sessions. For an unlimited wait time, specify 0.

Default: 120


  • Must be between 0 and 3600.

Type: Integer

Required: No


One or more SQL statements for the proxy to run when opening each new database connection. Typically used with SET statements to make sure that each connection has identical settings such as time zone and character set. For multiple statements, use semicolons as the separator. You can also include multiple variables in a single SET statement, such as SET x=1, y=2.

Default: no initialization query

Type: String

Required: No


The maximum size of the connection pool for each target in a target group. The value is expressed as a percentage of the max_connections setting for the RDS DB instance or Aurora DB cluster used by the target group.

If you specify MaxIdleConnectionsPercent, then you must also include a value for this parameter.

Default: 10 for RDS for Microsoft SQL Server, and 100 for all other engines


  • Must be between 1 and 100.

Type: Integer

Required: No


A value that controls how actively the proxy closes idle database connections in the connection pool. The value is expressed as a percentage of the max_connections setting for the RDS DB instance or Aurora DB cluster used by the target group. With a high value, the proxy leaves a high percentage of idle database connections open. A low value causes the proxy to close more idle connections and return them to the database.

If you specify this parameter, then you must also include a value for MaxConnectionsPercent.

Default: The default value is half of the value of MaxConnectionsPercent. For example, if MaxConnectionsPercent is 80, then the default value of MaxIdleConnectionsPercent is 40. If the value of MaxConnectionsPercent isn't specified, then for SQL Server, MaxIdleConnectionsPercent is 5, and for all other engines, the default is 50.


  • Must be between 0 and the value of MaxConnectionsPercent.

Type: Integer

Required: No


Each item in the list represents a class of SQL operations that normally cause all later statements in a session using a proxy to be pinned to the same underlying database connection. Including an item in the list exempts that class of SQL operations from the pinning behavior.

Default: no session pinning filters

Type: Array of strings

Required: No

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: