When a DTM process or the Data Integration Service process runs a job, it requests a connection instance from the pool. If an idle connection instance exists, the connection pool releases it to the DTM process or the Data Integration Service process. If the connection pool does not have an idle connection instance, the DTM process or the Data Integration Service process creates an active connection instance.
When the DTM process or the Data Integration Service process completes the job, it releases the active connection instance to the pool as an idle connection instance. If the connection pool contains the maximum number of idle connection instances, the process drops the active connection instance instead of releasing it to the pool.
The DTM process or the Data Integration Service process drops an idle connection instance from the pool when the following conditions are true:
A connection instance reaches the maximum idle time.
The connection pool exceeds the minimum number of idle connections.
When you update the user name, password, or connection string for a database connection that has connection pooling enabled, the updates take effect immediately. Subsequent connection requests use the updated information. Also, the connection pool library drops all idle connections and restarts the connection pool. It does not return any connection instances that are active at the time of the restart to the connection pool when complete.
If you update any other database connection property, you must restart the Data Integration Service to apply the updates.