[MAPREDUCE-7487] Missing System Output for Misconfiguration in KeyFieldBasedPartitioner Settings

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.3.6
• Component/s: mapreduce-client

Environment

Version: `3.3.6`
Location: hadoop/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/partition/KeyFieldBasedPartitioner.java， in `setConf` method, from Line 76 - 77.

• Assignee: Unassigned
• Reporter: LoggingResearch
• Created: 04/Sep/24 05:18
• Updated: 04/Sep/24 05:18

Description

To effectively use KeyFieldBasedPartitioner, users can optionally set the mapreduce.partition.keypartitioner.options configuration parameter to define partitioning behavior. However, this parameter is not documented in mapreduce-default.xml, leaving users without guidance on how to properly configure it. This omission hinders users from fully leveraging the system’s configurability.
 
Expected Behavior:
The system should provide warnings or informative logs to guide users in case of misconfiguration. Relying solely on users to carefully read through the configuration documentation is insufficient, particularly when the necessary details are not included in the documentation.
 
How-to-Fix:
To improve user experience, we suggest enhancing the system with additional logging to expose these configurations and their correct usage.