[
https://issues.apache.org/jira/browse/SPARK-32698?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Apache Spark reassigned SPARK-32698:
------------------------------------
Assignee: (was: Apache Spark)
> Do not fall back to default parallelism if the minimum number of coalesced
> partitions is not set in AQE
> -------------------------------------------------------------------------------------------------------
>
> Key: SPARK-32698
> URL: https://issues.apache.org/jira/browse/SPARK-32698
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 3.0.0
> Reporter: Manu Zhang
> Priority: Minor
>
> Currently in AQE when coalescing shuffling partitions,
> {quote}We fall back to Spark default parallelism if the minimum number of
> coalesced partitions is not set, so to avoid perf regressions compared to no
> coalescing.
> {quote}
> From our experience, this has resulted in a lot of uncertainty of the number
> of tasks after coalescing especially with dynamic allocation, and also lead
> to many small output files. It's complex and hard to reason about.
> Hence, I'm proposing not falling back to the default parallelism but
> coalescing towards the target size when the minimum number of coalesced
> partitions is not set.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
