In #963 (comment), @olavloite said that if a client is created with min sessions > 0, the client creation could fail. This is because we create the session pool before creating the database connection, and the database may not exist yet.

This means that we default to min=0 sessions so the client starts up with no sessions prepared and the first create session request is sent when the first request is received. In #963, a change was made to create sessions in batches of 10 (using BatchCreateSessions). So at least, the extra latency will only be experienced in fewer requests.

Ideally we should be able to set min > 0 sessions and have them be initialized before the first request.