Dongjoon Hyun a2c6adcc5d [SPARK-18857][SQL] Don't use Iterator.duplicate for incrementalCollect in Thrift Server ... ## What changes were proposed in this pull request? To support `FETCH_FIRST`, SPARK-16563 used Scala `Iterator.duplicate`. However, Scala `Iterator.duplicate` uses a **queue to buffer all items between both iterators**, this causes GC and hangs for queries with large number of rows. We should not use this, especially for `spark.sql.thriftServer.incrementalCollect`. https://github.com/scala/scala/blob/2.12.x/src/library/scala/collection/Iterator.scala#L1262-L1300 ## How was this patch tested? Pass the existing tests. Author: Dongjoon Hyun <dongjoon@apache.org> Closes #16440 from dongjoon-hyun/SPARK-18857.		2017-01-10 13:27:55 +00:00
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gen/java/org/apache/hive/service/cli/thrift	[SPARK-14987][SQL] inline hive-service (cli) into sql/hive-thriftserver	2016-04-29 09:32:42 -07:00
main	[SPARK-18857][SQL] Don't use Iterator.duplicate for incrementalCollect in Thrift Server	2017-01-10 13:27:55 +00:00
test	[SPARK-18992][SQL] Move spark.sql.hive.thriftServer.singleSession to SQLConf	2016-12-28 10:16:22 +08:00