We've decided to persist our domain model into database probably a year ago so beside the xml persistence our product uses any database system as a primary storage. The next step was key failure because we've designed the database schema according to current state of our domain model . Why not as NHibernate is so powerful that you are able to map almost every relation type, every scope of accessibility etc. Beside slow performance, I've already written those articles before, which we've fixed yet the another major issue appeared before a few months. The performance of MS SQL database during continuous insertion of medium-large rows slows down until the system appears almost dead. Why? As I've already written above, we've decided to not adjust the model according common database recommendations and just persist it. The lifecycle of our domain model needn't be usually coupled with database persistence. So all primary keys in all domain entities were absolu