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https://issues.apache.org/jira/browse/SPARK-34534?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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wuyi updated SPARK-34534:
-------------------------
    Target Version/s: 3.0.3

> New protocol FetchShuffleBlocks in OneForOneBlockFetcher lead to data loss or 
> correctness
> -----------------------------------------------------------------------------------------
>
>                 Key: SPARK-34534
>                 URL: https://issues.apache.org/jira/browse/SPARK-34534
>             Project: Spark
>          Issue Type: Bug
>          Components: Shuffle
>    Affects Versions: 3.0.0, 3.0.1, 3.0.2
>            Reporter: haiyangyu
>            Priority: Major
>              Labels: Correctness, data-loss
>             Fix For: 3.0.3, 3.1.2, 3.2.0
>
>         Attachments: image-2021-02-25-11-17-12-714.png, 
> image-2021-02-25-11-27-34-429.png, image-2021-02-25-11-28-31-255.png, 
> image-2021-02-25-11-30-03-834.png, image-2021-02-25-11-31-59-110.png
>
>
> We will build a new rpc message `FetchShuffleBlocks` when 
> `OneForOneBlockFetcher` init in replace of `OpenBlocks` to use adaptive 
> feature, this introduce additional problems as follows.
> `OneForOneBlockFetcher` will init a `blockIds` String array to catch chunk 
> fetch success, it will use index in `blockIds` to fetch blocks and match 
> blockId in `blockIds` when chunk data return. So the `blockIds` 's order must 
> be consistent with fetchChunk index, but the new `FetchShuffleBlocks` return 
> chunk order is not same as `blockIds`.
> This will lead to the return data not match the blockId,  and this can lead 
> to data corretness when retry to fetch after fetch block chunk failed.
> Fetch chunk orker code and match blockId when rerun data code as follows: 
> !image-2021-02-25-11-27-34-429.png|width=446,height=251!!image-2021-02-25-11-28-31-255.png|width=445,height=159!
> Howerver, the fetch order in shuffle service,
> !image-2021-02-25-11-30-03-834.png|width=510,height=361!
> So, it will fetch some wrong block data when chunk fetch failed beause the 
> blocks's wrong order.
> !image-2021-02-25-11-31-59-110.png|width=601,height=204!
>  
>  



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