[ 
https://issues.apache.org/jira/browse/SPARK-26089?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Apache Spark reassigned SPARK-26089:
------------------------------------

    Assignee:     (was: Apache Spark)

> Handle large corrupt shuffle blocks
> -----------------------------------
>
>                 Key: SPARK-26089
>                 URL: https://issues.apache.org/jira/browse/SPARK-26089
>             Project: Spark
>          Issue Type: Improvement
>          Components: Scheduler, Shuffle, Spark Core
>    Affects Versions: 2.4.0
>            Reporter: Imran Rashid
>            Priority: Major
>
> We've seen a bad disk lead to corruption in a shuffle block, which lead to 
> tasks repeatedly failing after fetching the data with an IOException.  The 
> tasks get retried, but the same corrupt data gets fetched again, and the 
> tasks keep failing.  As there isn't a fetch-failure, the jobs eventually 
> fail, spark never tries to regenerate the shuffle data.
> This is the same as SPARK-4105, but that fix only covered small blocks.  
> There was some discussion during that change about this limitation 
> (https://github.com/apache/spark/pull/15923#discussion_r88756017) and 
> followups to cover larger blocks (which would involve spilling to disk to 
> avoid OOM), but it looks like that never happened.
> I can think of a few approaches to this:
> 1) wrap the shuffle block input stream with another input stream, that 
> converts all exceptions into FetchFailures.  This is similar to the fix of 
> SPARK-4105, but that reads the entire input stream up-front, and instead I'm 
> proposing to do it within the InputStream itself so its streaming and does 
> not have a large memory overhead.
> 2) Add checksums to shuffle blocks.  This was proposed 
> [here|https://github.com/apache/spark/pull/15894] and abandoned as being too 
> complex.
> 3) Try to tackle this with blacklisting instead: when there is any failure in 
> a task that is reading shuffle data, assign some "blame" to the source of the 
> shuffle data, and eventually blacklist the source.  It seems really tricky to 
> get sensible heuristics for this, though.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

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

Reply via email to