[SQL] [SPARK-2826] Reduce the memory copy while building the hashmap for HashOuterJoin #1765
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QA tests have started for PR 1765. This patch merges cleanly. |
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QA results for PR 1765: |
| @@ -170,6 +164,9 @@ case class HashOuterJoin( | |||
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| def output = left.output ++ right.output | |||
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| @transient private[this] lazy val DUMMY_LIST = Seq[Row](null) | |||
| @transient private[this] lazy val EMPTY_LIST = Seq.empty[Row] | |||
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This is a fairly minor nit but defining EMPTY_LIST instead of just using Seq.empty[Row]
- Takes up extra space in the class
- Requires double checked locking / lazy initialization logic for each access
- Requires the developer to find the variable and figure out what it means, instead of
Seq.empty[Row]which is standard scala.
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Thank you @marmbrus , I will fix that as you suggested.
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I went ahead and merged this since it improves perf and my only comments were cosmetic. Thanks! |
asfgit
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…for HashOuterJoin This is a follow up for #1147 , this PR will improve the performance about 10% - 15% in my local tests. ``` Before: LeftOuterJoin: took 16750 ms ([3000000] records) LeftOuterJoin: took 15179 ms ([3000000] records) RightOuterJoin: took 15515 ms ([3000000] records) RightOuterJoin: took 15276 ms ([3000000] records) FullOuterJoin: took 19150 ms ([6000000] records) FullOuterJoin: took 18935 ms ([6000000] records) After: LeftOuterJoin: took 15218 ms ([3000000] records) LeftOuterJoin: took 13503 ms ([3000000] records) RightOuterJoin: took 13663 ms ([3000000] records) RightOuterJoin: took 14025 ms ([3000000] records) FullOuterJoin: took 16624 ms ([6000000] records) FullOuterJoin: took 16578 ms ([6000000] records) ``` Besides the performance improvement, I also do some clean up as suggested in #1147 Author: Cheng Hao <hao.cheng@intel.com> Closes #1765 from chenghao-intel/hash_outer_join_fixing and squashes the following commits: ab1f9e0 [Cheng Hao] Reduce the memory copy while building the hashmap (cherry picked from commit 5d54d71) Signed-off-by: Michael Armbrust <michael@databricks.com>
xiliu82
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Sep 4, 2014
…for HashOuterJoin This is a follow up for apache#1147 , this PR will improve the performance about 10% - 15% in my local tests. ``` Before: LeftOuterJoin: took 16750 ms ([3000000] records) LeftOuterJoin: took 15179 ms ([3000000] records) RightOuterJoin: took 15515 ms ([3000000] records) RightOuterJoin: took 15276 ms ([3000000] records) FullOuterJoin: took 19150 ms ([6000000] records) FullOuterJoin: took 18935 ms ([6000000] records) After: LeftOuterJoin: took 15218 ms ([3000000] records) LeftOuterJoin: took 13503 ms ([3000000] records) RightOuterJoin: took 13663 ms ([3000000] records) RightOuterJoin: took 14025 ms ([3000000] records) FullOuterJoin: took 16624 ms ([6000000] records) FullOuterJoin: took 16578 ms ([6000000] records) ``` Besides the performance improvement, I also do some clean up as suggested in apache#1147 Author: Cheng Hao <hao.cheng@intel.com> Closes apache#1765 from chenghao-intel/hash_outer_join_fixing and squashes the following commits: ab1f9e0 [Cheng Hao] Reduce the memory copy while building the hashmap
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This is a follow up for #1147 , this PR will improve the performance about 10% - 15% in my local tests.
Besides the performance improvement, I also do some clean up as suggested in #1147