You are viewing a plain text version of this content. The canonical link for it is here.

Posted to issues@spark.apache.org by "Apache Spark (JIRA)" <ji...@apache.org> on 2017/09/14 21:59:00 UTC

[jira] [Commented] (SPARK-22017) watermark evaluation with multi-input stream operators is unspecified

    [ https://issues.apache.org/jira/browse/SPARK-22017?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16167020#comment-16167020 ] 

Apache Spark commented on SPARK-22017:
--------------------------------------

User 'joseph-torres' has created a pull request for this issue:
https://github.com/apache/spark/pull/19239

> watermark evaluation with multi-input stream operators is unspecified
> ---------------------------------------------------------------------
>
>                 Key: SPARK-22017
>                 URL: https://issues.apache.org/jira/browse/SPARK-22017
>             Project: Spark
>          Issue Type: Bug
>          Components: Structured Streaming
>    Affects Versions: 2.2.0
>            Reporter: Jose Torres
>
> Watermarks are stored as a single value in StreamExecution. If a query has multiple watermark nodes (which can generally only happen with multi input operators like union), a headOption call will arbitrarily pick one to use as the real one. This will happen independently in each batch, possibly leading to strange and undefined behavior.
> We should instead choose the minimum from all watermark exec nodes as the query-wide watermark.



--
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