yarn 的学习路线,参考董的博客:http://dongxicheng.org/recommend/
hadoop2.0的进展和hadoop需要注意的东西参考: http://dongxicheng.org/mapreduce-nextgen/hadoop-2-new-feature-and-development/
HDFS进展 (1)对异构存储媒介的支持 (2)DataNode Cache (3)HDFS ACL (4)Rolling upgrade changes
YARN/MRv2进展 (1)Application History Server (2)对long-running application的支持(3)RM单点故障问题