Hadoop-0.21 版本, NEW FEATURES-Append设计文档.
关于Hadoop的Append功能相信有很多人都会觉得非常有用, 自从0.18.3版本支持Append, Hadoop在此功能上付出了剧痛的代价, 后来版本中, Hadoop干脆加了fs.append.support选项来禁止Append功能的使用.
当时Append功能的bug主要有下面几个
* HDFS-142 “Datanode should delete files under tmp when upgraded from 0.17″ * HADOOP-4692 “Namenode in infinite loop for replicating/deleting corrupted block” * HDFS-145 “FSNameSystem#addStoredBlock does not handle inconsistent block length correctly” * HDFS-168 “Block report processing should compare g[e]neration stamp”
