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Apache Spark commented on SPARK-2590: ------------------------------------- User 'liancheng' has created a pull request for this issue: https://github.com/apache/spark/pull/1853 > Add config property to disable incremental collection used in Thrift server > --------------------------------------------------------------------------- > > Key: SPARK-2590 > URL: https://issues.apache.org/jira/browse/SPARK-2590 > Project: Spark > Issue Type: Bug > Components: SQL > Reporter: Cheng Lian > Assignee: Cheng Lian > Priority: Blocker > > {{SparkSQLOperationManager}} uses {{RDD.toLocalIterator}} to collect the > result set one partition at a time. This is useful to avoid OOM when the > result is large, but introduces extra job scheduling costs as each partition > is collected with a separate job. Users may want to disable this when the > result set is expected to be small. > *UPDATE* Incremental collection hurts performance because tasks of the last > stage of the RDD DAG generated from the SQL query plan are executed > sequentially. Thus we decided to disable it by default. -- This message was sent by Atlassian JIRA (v6.2#6252) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org