[TAJO-691] HashJoin or HashAggregation is too slow if there is many unique keys

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.8.0, 0.9.0
• Assignee: Hyoungjun Kim
• Reporter: Hyoungjun Kim
• Created: 19/Mar/14 01:37
• Updated: 28/Mar/14 14:55
• Resolved: 28/Mar/14 14:43

Description

HashJoin or HashAggregation is too slow if there is many unique keys.
Java's native Map is inefficient to handle many items. In case more than 1 million items in HashMap, Adding 10000 items takes more than 7 ~ 10 seconds.
This should be improved.