氨气起动性能

nhibernate是在每次有人提出请求时分析XML文件,还是在应用程序启动时只分析一次?

好吧,我要做的是:

public class SessionManager
{
    private readonly ISessionFactory _sessionFactory;

    public SessionManager()
    {
        _sessionFactory = GetSessionFactory();
    }

    public ISession GetSession()
    {
        return _sessionFactory.OpenSession();
    }

    private static ISessionFactory GetSessionFactory()
    {
        return Fluently.Configure()
            .Database(MsSqlConfiguration.MsSql2005
                          .ConnectionString(c =>
                                            c.Is(
                                                @"Data Source=Pc-De-Yassir;Initial Catalog=MyDatabase;User Id=sa;Password=password;Integrated Security=True")
                          ))
            .Mappings(m =>
                      m.AutoMappings.Add
                          (
                          AutoPersistenceModel.MapEntitiesFromAssemblyOf<Model.Category>()
                          ))
            .BuildSessionFactory();
    }
}

下面是我如何从数据库中获取数据

public IList<Category> GetCategories()
    {
var session = new SessionManager().GetSession();
        return session.CreateCriteria(typeof(Category))
            .List<Category>();}

所以我的问题是,nhibernate会在第一次运行这个方法或每次发出请求时配置自己吗?