想在开发中使用NHibernate，但担心在性能上的问题，对查询的速度和Ado.Net进行了一下简单的比较。过程和代码如下描述，由于了解不深，暂不做结论，希望大家给点意见。

NHibernate HQL方式 : 830 条记录， 加载时间(ms) : 3334.7952  绑定IList时间(ms) : 70.1008
Ado.Net DbDataAdapter方式 : 830 条记录； 加载时间(ms) ： 40.0576  绑定IList时间(ms) ： 80.1152

测试环境：WinForm方式,数据库也在本机
硬件：CPU --  1.2G AMD duron(tm)          RAM -- 384M  DDR266
软件：Windows Server 2003, Sql Server 2000,Visual Studio.Net 2005

测试代码下载http://www.cnblogs.com/Files/liuyuanhuo/NHibernateTest_Performance.rar

测试的代码是在
子非鱼 NHibernate学习 http://sifang2004.cnblogs.com/archive/2005/09/05/230713.aspx
NHibernate 博客园专题之一  http://www.cnblogs.com/Files/sifang2004/NHibernateTest.rar
中下载的示例中作修改的。

测试由两个工程组成，
一.NHibernateTest工程，仅修改两个地方
 1.注释Order.hbm.xml中_Items相关的<bag元素
 2.在Order.cs增加下面两个方法

        /**//// <summary>
        /// 使用NHibernate HQL方式查询
        /// </summary>
        /// <returns>IList,订单对象集合</returns>
        public IList LoadAllByNHibernate()
        {
            IList orders = ObjectLoader.Find( " from Order ", null);
            return orders;
        }

        /**//// <summary>
        /// 使用Ado.Net DbDataAdapter方式查询
        /// </summary>
        /// <returns>DataTable,订单数据表</returns>
        public DataTable LoadAllByAdoNet()
        {
            DataTable dtOrders = new DataTable();

            DbConnection dbConnection = new SqlConnection();
            dbConnection.ConnectionString =
                        @"Server=Andy\Andy;initial catalog=Northwind;User id =sa;PassWord=sa";

            DbCommand dbCommand = new SqlCommand();
            dbCommand.Connection = dbConnection;
            dbCommand.CommandType = CommandType.Text;
            dbCommand.CommandText = "SELECT * FROM Orders";

            DbDataAdapter dataAdapter = new SqlDataAdapter();
            dataAdapter.SelectCommand = dbCommand;

            dataAdapter.Fill( dtOrders );

            return dtOrders;
        }

二.添加一个NHibernateTestUI工程，引用NHibernateTest，从NHibernateTest复制一份app.config到NHibernateTestUI，修改连接串，然后添加一个窗体类，加了两个按钮一个DataGridView, 两个按钮分别测试Ado.Net DbDataAdapter方式和NHibernate HQL方式的加载时间，测试代码如下:

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace NHibernateTestUI
{
    public partial class OrderFrm : Form
    {
        public OrderFrm()
        {
            InitializeComponent();
        }

        NHibernateTest.Order order = new NHibernateTest.Order();

        /**//// <summary>
        /// 使用NHibernate HQL方式查询
        /// </summary>
        PRivate void btnNHLoad_Click( object sender, EventArgs e )
        {
            string strOutput = "";

            // 测试加载数据时间
            DateTime dtStart = System.DateTime.Now;
            IList orders = order.LoadAllByNHibernate(); // 使用NHibernate HQL方式查询
            DateTime dtEnd = System.DateTime.Now;
            TimeSpan ts = dtEnd - dtStart;
            strOutput += "NHibernate HQL方式 : "
                + orders.Count + " 条记录， 加载时间(ms) : "
                + ts.TotalMilliseconds;

            // 测试绑定数据时间
            dtStart = System.DateTime.Now;
            this.dgvOrders.DataSource = orders;
            dtEnd = System.DateTime.Now;
            ts = dtEnd - dtStart;
            strOutput += "  绑定IList时间 : " + ts.TotalMilliseconds;

            Console.WriteLine( strOutput );
        }

        /**//// <summary>
        /// 使用Ado.Net DbDataAdapter方式查询
        /// </summary>
        private void btnADOLoad_Click( object sender, EventArgs e )
        {
            string strOutput = "";

            // 测试加载数据时间
            DateTime dtStart = System.DateTime.Now;
            DataTable dtOrders = order.LoadAllByAdoNet();   // 使用Ado.Net DbDataAdapter方式查询
            DateTime dtEnd = System.DateTime.Now;
            TimeSpan ts = dtEnd - dtStart;
            strOutput += "Ado.Net DbDataAdapter方式 : "
                + dtOrders.Rows.Count + " 条记录； 加载时间(ms) ： "
                + ts.TotalMilliseconds;

            // 测试绑定数据时间
            dtStart = System.DateTime.Now;
            this.dgvOrders.DataSource = dtOrders;
            dtEnd = System.DateTime.Now;
            ts = dtEnd - dtStart;
            strOutput += "  绑定IList时间 ： " + ts.TotalMilliseconds;

            Console.WriteLine( strOutput );
        }
    }
}

运行后界面如下：

在界面两个按钮点击多次后，两者的查询时间稳定，可以作为比较。下面是输出：
NHibernate :select order0_.orderId as orderId, order0_.shippedDate as shippedD4_, order0_.shipPostalCode as shipPos10_, order0_.requiredDate as required3_, order0_.shipCountry as shipCou11_, order0_.shipVia as shipVia, order0_.orderDate as orderDate, order0_.shipAddress as shipAddr7_, order0_.shipRegion as shipRegion, order0_.shipName as shipName, order0_.shipCity as shipCity, order0_.customerId as customerId, order0_.freight as freight, order0_.employeeId as employeeId from Orders order0_
NHibernate HQL方式 : 830 条记录， 加载时间(ms) : 3334.7952  绑定IList时间 : 70.1008
NHibernate :select order0_.orderId as orderId, order0_.shippedDate as shippedD4_, order0_.shipPostalCode as shipPos10_, order0_.requiredDate as required3_, order0_.shipCountry as shipCou11_, order0_.shipVia as shipVia, order0_.orderDate as orderDate, order0_.shipAddress as shipAddr7_, order0_.shipRegion as shipRegion, order0_.shipName as shipName, order0_.shipCity as shipCity, order0_.customerId as customerId, order0_.freight as freight, order0_.employeeId as employeeId from Orders order0_
NHibernate HQL方式 : 830 条记录， 加载时间(ms) : 3304.752  绑定IList时间 : 70.1008
NHibernate :select order0_.orderId as orderId, order0_.shippedDate as shippedD4_, order0_.shipPostalCode as shipPos10_, order0_.requiredDate as required3_, order0_.shipCountry as shipCou11_, order0_.shipVia as shipVia, order0_.orderDate as orderDate, order0_.shipAddress as shipAddr7_, order0_.shipRegion as shipRegion, order0_.shipName as shipName, order0_.shipCity as shipCity, order0_.customerId as customerId, order0_.freight as freight, order0_.employeeId as employeeId from Orders order0_
NHibernate HQL方式 : 830 条记录， 加载时间(ms) : 3354.824  绑定IList时间 : 80.1152
Ado.Net DbDataAdapter方式 : 830 条记录； 加载时间(ms) ： 40.0576  绑定IList时间 ： 80.1152
Ado.Net DbDataAdapter方式 : 830 条记录； 加载时间(ms) ： 40.0576  绑定IList时间 ： 90.1296
Ado.Net DbDataAdapter方式 : 830 条记录； 加载时间(ms) ： 30.0432  绑定IList时间 ： 90.1296
NHibernate :select order0_.orderId as orderId, order0_.shippedDate as shippedD4_, order0_.shipPostalCode as shipPos10_, order0_.requiredDate as required3_, order0_.shipCountry as shipCou11_, order0_.shipVia as shipVia, order0_.orderDate as orderDate, order0_.shipAddress as shipAddr7_, order0_.shipRegion as shipRegion, order0_.shipName as shipName, order0_.shipCity as shipCity, order0_.customerId as customerId, order0_.freight as freight, order0_.employeeId as employeeId from Orders order0_
NHibernate HQL方式 : 830 条记录， 加载时间(ms) : 3334.7952  绑定IList时间 : 70.1008
Ado.Net DbDataAdapter方式 : 830 条记录； 加载时间(ms) ： 50.072  绑定IList时间 ： 90.1296

另外在网上找了一下关于NHibernate性能的讨论的有，
http://kevin-y.cnblogs.com/archive/2006/02/08/327164.html
http://wljcan.cnblogs.com/archive/2005/05/14/155495.aspx
很少，希望能有已经做过NHibernate考量的高手提供点路子，非常感谢。