[HADOOP-1762] Namenode does not need to store storageID and datanodeID persistently

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.14.0
• Fix Version/s: 0.15.0
• Assignee: Raghu Angadi
• Reporter: Raghu Angadi
• Created: 22/Aug/07 22:19
• Updated: 16/Apr/13 15:51
• Resolved: 18/Sep/07 06:40

Description

Currently Namenode stores all the storage-ids it generates since the beginning (since last format). It allocates a new storageID everytime a new datanode comes online. It also stores all the known datanode ids since the beginning.

It would be better if Namenode did not have to keep track of these. I will describe a proposal in the next comment.

This has implecations regd how Namenode helps administrators identify 'dead datanodes' etc. These issues are addressed in HADOOP-1138.

Issue Links

• relates to: HDFS-4702 remove namesystem lock from DatanodeManager#fetchDatanodes