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https://issues.apache.org/jira/browse/HIVE-22411?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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László Bodor updated HIVE-22411:
--------------------------------
    Component/s: Transactions

> Performance degradation on single row inserts
> ---------------------------------------------
>
>                 Key: HIVE-22411
>                 URL: https://issues.apache.org/jira/browse/HIVE-22411
>             Project: Hive
>          Issue Type: Bug
>          Components: Hive, Transactions
>            Reporter: Attila Magyar
>            Assignee: Attila Magyar
>            Priority: Major
>             Fix For: 4.0.0
>
>         Attachments: HIVE-22411.2.patch, HIVE-22411.3.patch, Screen Shot 
> 2019-10-17 at 8.40.50 PM.png
>
>
> Executing single insert statements on a transactional table effects write 
> performance on a s3 file system. Each insert creates a new delta directory. 
> After each insert hive calculates statistics like number of file in the table 
> and total size of the table. In order to calculate these, it traverses the 
> directory recursively. During the recursion for each path a separate 
> listStatus call is executed. In the end the more delta directory you have the 
> more time it takes to calculate the statistics.
> Therefore insertion time goes up linearly:
> !Screen Shot 2019-10-17 at 8.40.50 PM.png|width=601,height=436!
> The fix is to use fs.listFiles(path, /**recursive**/ true) instead the 
> handcrafter recursive method/



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