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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if	[MINOR][MLLIB][STREAMING][SQL] Fix typos	2016-05-25 10:53:57 -07:00
src	[SPARK-18857][SQL] Don't use Iterator.duplicate for incrementalCollect in Thrift Server	2017-01-10 13:27:55 +00:00
pom.xml	[SPARK-17807][CORE] split test-tags into test-JAR	2016-12-21 16:37:20 -08:00