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Apache Spark commented on SPARK-34253: -------------------------------------- User 'c21' has created a pull request for this issue: https://github.com/apache/spark/pull/31353 > Object hash aggregate should not fallback if no more input rows > --------------------------------------------------------------- > > Key: SPARK-34253 > URL: https://issues.apache.org/jira/browse/SPARK-34253 > Project: Spark > Issue Type: Improvement > Components: SQL > Affects Versions: 3.2.0 > Reporter: Cheng Su > Priority: Trivial > > Object hash aggregate will fallback to sort-based aggregation based on number > of keys seen so far [0]. The default config threshold is 128 > (spark.sql.objectHashAggregate.sortBased.fallbackThreshold in [1]). There's > an edge case we can do better, where we do not fallback if there's no more > input rows. Suppose the task only has 128 group-by keys in hash ma, we don't > need to fallback in this case, and we can save the extra sort. > > [0]: > [https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/aggregate/ObjectAggregationIterator.scala#L161] > > [1]: > [https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala#L1615] > -- 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