As I have read somewhere on the forum, by not specifying the "hibernate.pool_size" parameter, database connection pooling would be turned off. I would expect Hibernate to create a connection for every session that is opened. This does not seem to be the case. Hibernate seems to create one connection and then retain that connection, which causes my application to suffer from the usual connection timeout issues.

Is there another way to totally disable connection pooling?

Just set "hibernate.pool_size" parameter to zero.

Hibernate internal pool is very simple. It only checks this value when connection needs to be closed. So, if number of opened connections is not larger than "hibernate.pool_size" it retains connection in the open state. Setting the parameter to zero resolves this issue.

It is not possible to turn off the pooling at all (except by writing your own connection open provider or feeding connections to hibernate SessionFactory object yourself), but this solution should be fully enough for you.

If you want more technical details you can check out the code of following objects:

DriverManagerConnectionProvider - this is default pool provider,
SettingsFactory - this class chooses connection pool provider for you.