[HDFS-6529] Trace logging for RemoteBlockReader2 to identify remote datanode and file being read

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.4.0
• Fix Version/s: 2.5.0
• Component/s: hdfs-client
• Target Version/s: 2.5.0
• Hadoop Flags: Reviewed
• Assignee: Anubhav Dhoot
• Reporter: Anubhav Dhoot
• Created: 13/Jun/14 20:34
• Updated: 15/Aug/14 05:41
• Resolved: 14/Jun/14 01:00

Description

The scenario is some download is stuck and we dont know which data node is the client waiting and for which path.
By turning this file trace logging we will get a running trace of which requests have started and which have completed.
If trace is not enabled, there is no overhead other than checking if trace is enabled