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https://issues.apache.org/jira/browse/TEZ-2574?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14606306#comment-14606306
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Saikat commented on TEZ-2574:
-----------------------------

Thanks for the review comments. Will work on the suggested approach.
One comment about the small split sizes of 1M entries, I had added the 
following logic
"In order to keep the splits small(according to existing implementation), a min 
comparison is performed between desired items(1M) and new number items is 
calculated. min(1M, numitems))"

> Make a better Metadata Value split choice in Pipeline sort
> ----------------------------------------------------------
>
>                 Key: TEZ-2574
>                 URL: https://issues.apache.org/jira/browse/TEZ-2574
>             Project: Apache Tez
>          Issue Type: Improvement
>            Reporter: Saikat
>            Assignee: Saikat
>         Attachments: TEZ-2574.patch
>
>
> In the current implementation of pipeline sort, when a new sort span object 
> is created with a hard coded value of 1M items and 16 bytes per item.
> According to the present code logic, 
>       int metasize = METASIZE*maxItems;
>       int dataSize = maxItems * perItem;
>       if(capacity < (metasize+dataSize)) {
>         // try to allocate less meta space, because we have sample data
>         metasize = METASIZE*(capacity/(perItem+METASIZE));
>       }
> if capacity is less than 32mb, the buffer will be halved into meta and value 
> buffers, which is not efficient.
> We need a more generic split, based on the KV pair size written to the buffer.



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