[ 
https://issues.apache.org/jira/browse/PIG-4148?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Cheolsoo Park reassigned PIG-4148:
----------------------------------

    Assignee:     (was: Cheolsoo Park)

> Tez order-by is often skewed because FindQuantiles UDF is called with small 
> number
> ----------------------------------------------------------------------------------
>
>                 Key: PIG-4148
>                 URL: https://issues.apache.org/jira/browse/PIG-4148
>             Project: Pig
>          Issue Type: Sub-task
>          Components: tez
>            Reporter: Cheolsoo Park
>             Fix For: 0.14.0
>
>
> In Tez, FindQuantiles UDF is called with a smaller number of samples than MR 
> resulting in skew in range partitions.
> For example, I have a job that runs sampling with a parallelism of 300. Since 
> each task samples 100 records, the total sample should be 30K. But 
> FindQuantiles UDF is called with only 300 samples.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to