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https://issues.apache.org/jira/browse/SPARK-25299?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16729292#comment-16729292
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Peiyu Zhuang commented on SPARK-25299:
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We are currently working on a solution that is similar to option 3 mentioned in 
this [architecture discussion 
document|https://docs.google.com/document/d/1uCkzGGVG17oGC6BJ75TpzLAZNorvrAU3FRd2X-rVHSM/edit#heading=h.btqugnmt2h40].
  The idea is to refactor the current shuffle manager and extract a common 
storage interface.  User could supply different storage implementations for 
shuffle data and spill data.
We have got some preliminary test result.  Since shuffle manager is critical to 
Spark, we want to make sure it functions just as the original shuffle manager.  
And it will be open-sourced in the near future.


> Use remote storage for persisting shuffle data
> ----------------------------------------------
>
>                 Key: SPARK-25299
>                 URL: https://issues.apache.org/jira/browse/SPARK-25299
>             Project: Spark
>          Issue Type: New Feature
>          Components: Shuffle
>    Affects Versions: 2.4.0
>            Reporter: Matt Cheah
>            Priority: Major
>
> In Spark, the shuffle primitive requires Spark executors to persist data to 
> the local disk of the worker nodes. If executors crash, the external shuffle 
> service can continue to serve the shuffle data that was written beyond the 
> lifetime of the executor itself. In YARN, Mesos, and Standalone mode, the 
> external shuffle service is deployed on every worker node. The shuffle 
> service shares local disk with the executors that run on its node.
> There are some shortcomings with the way shuffle is fundamentally implemented 
> right now. Particularly:
>  * If any external shuffle service process or node becomes unavailable, all 
> applications that had an executor that ran on that node must recompute the 
> shuffle blocks that were lost.
>  * Similarly to the above, the external shuffle service must be kept running 
> at all times, which may waste resources when no applications are using that 
> shuffle service node.
>  * Mounting local storage can prevent users from taking advantage of 
> desirable isolation benefits from using containerized environments, like 
> Kubernetes. We had an external shuffle service implementation in an early 
> prototype of the Kubernetes backend, but it was rejected due to its strict 
> requirement to be able to mount hostPath volumes or other persistent volume 
> setups.
> In the following [architecture discussion 
> document|https://docs.google.com/document/d/1uCkzGGVG17oGC6BJ75TpzLAZNorvrAU3FRd2X-rVHSM/edit#heading=h.btqugnmt2h40]
>  (note: _not_ an SPIP), we brainstorm various high level architectures for 
> improving the external shuffle service in a way that addresses the above 
> problems. The purpose of this umbrella JIRA is to promote additional 
> discussion on how we can approach these problems, both at the architecture 
> level and the implementation level. We anticipate filing sub-issues that 
> break down the tasks that must be completed to achieve this goal.



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