[HADOOP-4842] Streaming combiner should allow command, not just JavaClass

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.21.0
• Hadoop Flags: Reviewed
• Release Note: Streaming option -combiner allows any streaming command (not just Java class) to be a combiner.
• Assignee: Amareshwari Sriramadasu
• Reporter: Marco Nicosia
• Created: 11/Dec/08 23:07
• Updated: 29/Jun/12 20:53
• Resolved: 19/Mar/09 11:20

Description

Streaming jobs are way slower than Java jobs for many reasons, but certainly stopping the shell-only programmer from using the combiner feature won't help. Right now, the streaming usage says:

-mapper <cmd|JavaClassName> The streaming command to run
-combiner <JavaClassName> Combiner has to be a Java class
-reducer <cmd|JavaClassName> The streaming command to run