http://www.ibm.com/developerworks/cn/linux/l-memory/
http://baike.baidu.com/view/4541016.htm
http://baike.baidu.com/view/1082.htm
http://blog.csdn.net/kanghua/archive/2007/10/22/1837872.aspx
http://articles.e-works.net.cn/411/Article171
http://www.ibm.com/developerworks/cn/linux/l-memory/
http://baike.baidu.com/view/4541016.htm
http://baike.baidu.com/view/1082.htm
http://blog.csdn.net/kanghua/archive/2007/10/22/1837872.aspx
http://articles.e-works.net.cn/411/Article171