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https://issues.apache.org/jira/browse/FLINK-1725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14720719#comment-14720719
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ASF GitHub Bot commented on FLINK-1725:
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Github user anisnasir commented on the pull request:

    https://github.com/apache/flink/pull/1069#issuecomment-135905274
  
    @tillrohrmann you are absolutely right with your observation that high 
skews require more than two workers to process the most frequent keys. However, 
most of the real world datasets do not have high skews [1] and can be handled 
by just splitting keys into two components.
    
    I was planning to write a wordcount example with both HashPartitioner and 
PartialPartitioner. Can you explain a little more on how one could check that 
the skew of the input data decreases after the partitioning.
    
    [1]. 
https://melmeric.files.wordpress.com/2014/11/the-power-of-both-choices-practical-load-balancing-for-distributed-stream-processing-engines.pdf


> New Partitioner for better load balancing for skewed data
> ---------------------------------------------------------
>
>                 Key: FLINK-1725
>                 URL: https://issues.apache.org/jira/browse/FLINK-1725
>             Project: Flink
>          Issue Type: Improvement
>          Components: New Components
>    Affects Versions: 0.8.1
>            Reporter: Anis Nasir
>            Assignee: Anis Nasir
>              Labels: LoadBalancing, Partitioner
>   Original Estimate: 336h
>  Remaining Estimate: 336h
>
> Hi,
> We have recently studied the problem of load balancing in Storm [1].
> In particular, we focused on key distribution of the stream for skewed data.
> We developed a new stream partitioning scheme (which we call Partial Key 
> Grouping). It achieves better load balancing than key grouping while being 
> more scalable than shuffle grouping in terms of memory.
> In the paper we show a number of mining algorithms that are easy to implement 
> with partial key grouping, and whose performance can benefit from it. We 
> think that it might also be useful for a larger class of algorithms.
> Partial key grouping is very easy to implement: it requires just a few lines 
> of code in Java when implemented as a custom grouping in Storm [2].
> For all these reasons, we believe it will be a nice addition to the standard 
> Partitioners available in Flink. If the community thinks it's a good idea, we 
> will be happy to offer support in the porting.
> References:
> [1]. 
> https://melmeric.files.wordpress.com/2014/11/the-power-of-both-choices-practical-load-balancing-for-distributed-stream-processing-engines.pdf
> [2]. https://github.com/gdfm/partial-key-grouping



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