[
https://issues.apache.org/jira/browse/SPARK-17480?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Ergin Seyfe updated SPARK-17480:
--------------------------------
Description:
When we profile one of our Spark jobs we saw that:
6.24% of the CPU is spend on List.length.
Scala List's length method is O(N) =>
https://github.com/scala/scala/blob/2.10.x/src/library/scala/collection/LinearSeqOptimized.scala#L36
Since we loop this method becomes O(N^2)
was:
When we profile one of our Spark jobs we saw that:
6.24% of the CPU is spend on List.length.
Scala List's length method is O (N) =>
https://github.com/scala/scala/blob/2.10.x/src/library/scala/collection/LinearSeqOptimized.scala#L36
Since we loop this method becomes O(N^2)
> CompressibleColumnBuilder inefficiently call gatherCompressibilityStats
> ------------------------------------------------------------------------
>
> Key: SPARK-17480
> URL: https://issues.apache.org/jira/browse/SPARK-17480
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Reporter: Ergin Seyfe
> Priority: Minor
>
> When we profile one of our Spark jobs we saw that:
> 6.24% of the CPU is spend on List.length.
> Scala List's length method is O(N) =>
> https://github.com/scala/scala/blob/2.10.x/src/library/scala/collection/LinearSeqOptimized.scala#L36
> Since we loop this method becomes O(N^2)
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
