[HDFS-543] Break FSDatasetInterface#writeToBlock() into writeToTemporary, writeToRBW, and append

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Append Branch
• Fix Version/s: Append Branch
• Component/s: datanode
• Hadoop Flags: Reviewed
• Assignee: Hairong Kuang
• Reporter: Hairong Kuang
• Created: 12/Aug/09 18:32
• Updated: 30/Aug/09 23:24
• Resolved: 30/Aug/09 23:23

Description

FSDatasetInterface#writeToBlock() currently allows to create/recover a temporary replica, create/recover a RBW replica, or append to a replica. The implementation of the method in FSDataset is very complicated and error prone. I'd like to break this method into 3:
1. writeToTemporary allows to create a Temporary replica or recover from a packet error for a Tempoary replica;
2. writeToRBW allows to create a RBW replica or recover from a packet error for a RBW replica;
3. append allows to append to an existing Finalized replica.