Hortonworks 启动 Hadoop-0.23
slide：http://www.slideshare.net/hortonworks/apache-hadoop-023
blog：http://www.hortonworks.com/preparing-for-next-release-of-apache-hadoop/
svn：http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.23/
HDFS Federation：
slide：http://www.slideshare.net/hortonworks/hs-2011-submission87hwfinal
blog：http://www.hortonworks.com/an-introduction-to-hdfs-federation/
NextGen MapReduce
slide：http://www.slideshare.net/hortonworks/nextgen-apache-hadoop-mapreduce
blog：http://www.hortonworks.com/nextgen-mapreduce-hits-apache-hadoop-mainline/
两个主要的jira：
1、HDFS High Availablity
https://issues.apache.org/jira/browse/HDFS-1623
高可用方案与Facebook的Avatar实现一样
http://borthakur.com/ftp/RealtimeHadoopSigmod2011.pdf
（DBRD方案：http://www.drbd.org/）
2、Editlogs rewrite
https://issues.apache.org/jira/browse/HDFS-1073
hadoop summit上的slide：
http://www.hortonworks.com/hadoop-summit-presentations/
