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https://issues.apache.org/jira/browse/FLINK-3480?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Greg Hogan updated FLINK-3480:
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    Comment: was deleted

(was: Today I bumped into the performance discrepancy where a forwarding ship 
strategy can hurt performance since we can only do a sorted reduce whereas with 
a partition hash we can use the new hash-combiner.

What would be the spilling strategy for a hash-reducer and would this look much 
different from using the hash-combiner followed by the sort-reducer?)

> Add hash-based strategy for ReduceFunction
> ------------------------------------------
>
>                 Key: FLINK-3480
>                 URL: https://issues.apache.org/jira/browse/FLINK-3480
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Local Runtime
>            Reporter: Fabian Hueske
>
> This issue is related to FLINK-3477. 
> While FLINK-3477 proposes to add hash-based combine strategy for 
> ReduceFunction, this issue aims to add a hash-based strategy for the final 
> aggregation.
> This will need again a special hash-table aggregation which allows for 
> in-place updates and append updates. However, it also needs to support 
> spilling to disk in case of too tight memory budgets.



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