缓存同步怎么理解

http://readwall.blog.163.com/blog/static/1012713220118302265695/

redis缓存保存在硬盘，重启服务器缓存不会丢失。

http://zlf140.blog.163.com/blog/static/140659220095835828222/

http://www.cnblogs.com/mxw09/archive/2011/08/16/2141457.html