[HIVE-6222] Make Vector Group By operator abandon grouping if too many distinct keys

• Type: Sub-task
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.13.0
• Fix Version/s: 0.13.0
• Component/s: Query Processor
• Labels: vectorization
• Hadoop Flags: Reviewed
• Assignee: Remus Rusanu
• Reporter: Remus Rusanu
• Created: 17/Jan/14 17:51
• Updated: 23/Mar/14 18:35
• Resolved: 22/Mar/14 08:09

Description

Row mode GBY is becoming a pass-through if not enough aggregation occurs on the map side, relying on the shuffle+reduce side to do the work. Have VGBY do the same.