spark-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Xiao Li (JIRA)" <j...@apache.org>
Subject [jira] [Reopened] (SPARK-22411) Heuristic to combine splits in DataSourceScanExec isn't accurate when dynamic allocation is enabled
Date Sat, 04 Nov 2017 18:13:01 GMT

     [ https://issues.apache.org/jira/browse/SPARK-22411?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Xiao Li reopened SPARK-22411:
-----------------------------

> Heuristic to combine splits in DataSourceScanExec isn't accurate when dynamic allocation
is enabled
> ---------------------------------------------------------------------------------------------------
>
>                 Key: SPARK-22411
>                 URL: https://issues.apache.org/jira/browse/SPARK-22411
>             Project: Spark
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 2.0.0
>            Reporter: Vinitha Reddy Gankidi
>            Assignee: Vinitha Reddy Gankidi
>            Priority: Major
>             Fix For: 2.3.0
>
>
> The heuristic to calculate the maxSplitSize in DataSourceScanExec is as follows:
> https://github.com/apache/spark/blob/d28d5732ae205771f1f443b15b10e64dcffb5ff0/sql/core/src/main/scala/org/apache/spark/sql/execution/DataSourceScanExec.scala#L431
> Default parallelism in this case is the number of total cores of all the registered executors
for this application. This works well with static allocation but with dynamic allocation enabled,
this value is usually one (with default config of min and initial executors as zero) at the
time of split calculation. This heuristic was introduced in SPARK-14582. 
> When Dynamic allocation it is confusing to tune the split size with this heuristic. It
is better to ignore bytesPerCore and use the values of 'spark.sql.files.maxPartitionBytes'
as the max split size. 



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org


Mime
View raw message