[MAPREDUCE-2637] Providing options to debug the mapreduce user code (Mapper, Reducer, Combiner, Sort implementations)

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: tasktracker
• Assignee: Devaraj Kavali
• Reporter: Devaraj Kavali
• Created: 01/Jul/11 15:10
• Updated: 18/May/12 20:19

Description

Presently Hadoop provides "mapred.child.java.opts" configuration which can be used to set JVM options for Child JVM running Map or Reduce Task.
If we need to remote debug the Child JVM, we can add remote debugging options to this configuration value.
But this will work only for single Child JVM. Other children will fail as the remote debugging port is already used.
We cannot specify the remote debugging port dynamically.
As a result, it's not possible to remote debug multiple Child JVMs.
As a solution to this problem, we can provide a configuration to debug Task JVMs in this scenario.

Issue Links

• is related to: MAPREDUCE-2606 Remove IsolationRunner