[MAPREDUCE-3678] The Map tasks logs should have the value of input split it processed

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0, 2.0.0-alpha
• Fix Version/s: 1.2.0, 2.0.3-alpha
• Component/s: mrv1, mrv2
• Hadoop Flags: Reviewed
• Release Note: A map-task's syslogs now carries basic info on the InputSplit it processed.
• Assignee: Harsh J
• Reporter: Bejoy KS
• Created: 16/Jan/12 17:35
• Updated: 15/Feb/13 13:10
• Resolved: 09/Oct/12 13:45

Description

It would be easier to debug some corner in tasks if we knew what was the input split processed by that task. Map reduce task tracker log should accommodate the same. Also in the jobdetails web UI, the split also should be displayed along with the Split Locations.

Sample as
Input Split
hdfs://myserver:9000/userdata/sampleapp/inputdir/file1.csv - <split no>/<offset from beginning of file>

This would be much beneficial to nail down some data quality issues in large data volume processing.

Issue Links

• duplicates: MAPREDUCE-2076 Showing inputsplit filename/offset inside the webui or tasklog