官网:http://www.cnblogs.com/langtianya/p/5199529.html
总体介绍:http://www.cnblogs.com/langtianya/p/5199529.html
各个组件:http://www.cnblogs.com/xymqx/p/4374909.html
ack原理:https://my.oschina.net/u/2000675/blog/609147
分组:http://www.cnblogs.com/xymqx/p/4365190.html