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Series of .NET NHibernate performance issues articles

I've spent with NHibernate persistence implementation to our product last four months. I'd like to provide set of articles regarding performance issues of the NHibernate usage.

NHibernate team has been releasing huge manual having 189 pages. It contains the basic description allowing the developer to write persistence and not totally mess it up. If you want to develop fast application, you need to read discussions (such as those at and solve the problems particularly one by one. According to my experiences, I've decide to write the series of articles regarding NHibernate, especially performance.

All following articles will contain examples. I love so it's nonsense to do not use it because it's fine integrated together as well as log4net.

All examples which will be described or used in the whole series will use three classes as domain model. According to Domain Driven Design, there are root aggregate Library, child Book and it's child Rental. Don't linger on various circumstances like book's author should be separated aggregate or library is identified by it's name. Already, it's certainly that domain model needs to be changed because there are still no identificator at the database level.

Following picture defines relations between all domain classes, standard UML:

Examples at
All examples are placed at, see:

All series part
  1. NHibernate performance issues #1: evil List (non-inverse relationhip)
  2. NHibernate performance issues #2: slow cascade save and update (flushing)
  3. NHibernate performance issues #3: slow inserts (stateless session)
  4. NHibernate performance issues #4: slow query compilation - named queries


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