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Apache Spark commented on SPARK-35141: -------------------------------------- User 'c21' has created a pull request for this issue: https://github.com/apache/spark/pull/34270 > Support two level map for final hash aggregation > ------------------------------------------------ > > Key: SPARK-35141 > URL: https://issues.apache.org/jira/browse/SPARK-35141 > Project: Spark > Issue Type: Improvement > Components: SQL > Affects Versions: 3.2.0 > Reporter: Cheng Su > Assignee: Cheng Su > Priority: Minor > Fix For: 3.2.0 > > > For partial hash aggregation (code-gen path), we have two level of hash map > for aggregation. First level is from `RowBasedHashMapGenerator`, which is > computation faster compared to the second level from > `UnsafeFixedWidthAggregationMap`. The introducing of two level hash map can > help improve CPU performance of query as the first level hash map normally > fits in hardware cache and has cheaper hash function for key lookup. > For final hash aggregation, we can also support two level of hash map, to > improve query performance further. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org