[ 
https://issues.apache.org/jira/browse/SPARK-23996?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16444909#comment-16444909
 ] 

Miao Wang edited comment on SPARK-23996 at 4/19/18 10:34 PM:
-------------------------------------------------------------

[~timhunter] There is a Java implementation: 
[https://github.com/DataSketches/sketches-core/tree/master/src/main/java/com/yahoo/sketches/kll]

I am reading the code now.

Is 
[QuantileSummaries.scala|https://github.com/apache/spark/pull/15002/files#diff-48cfea2315f9ae39c33801873c4dbf84]
 your implementation?

Thanks!

Miao


was (Author: wm624):
[~timhunter] There is a Java implementation: 
[https://github.com/DataSketches/sketches-core/tree/master/src/main/java/com/yahoo/sketches/kll]

I am reading the code now.

Can you point me your spark implementation?

Thanks!

Miao

> Implement the optimal KLL algorithms for quantiles in streams
> -------------------------------------------------------------
>
>                 Key: SPARK-23996
>                 URL: https://issues.apache.org/jira/browse/SPARK-23996
>             Project: Spark
>          Issue Type: Improvement
>          Components: MLlib, SQL
>    Affects Versions: 2.3.0
>            Reporter: Timothy Hunter
>            Priority: Major
>
> The current implementation for approximate quantiles - a variant of 
> Grunwald-Khanna, which I implemented - is not the best in light of recent 
> papers:
>  - it is not exactly the one from the paper for performance reasons, but the 
> changes are not documented beyond comments on the code
>  - there are now more optimal algorithms with proven bounds (unlike q-digest, 
> the other contender at the time)
> I propose that we revisit the current implementation and look at the 
> Karnin-Lang-Liberty algorithm (KLL) for example:
> [https://arxiv.org/abs/1603.05346]
> [https://edoliberty.github.io//papers/streamingQuantiles.pdf]
> This algorithm seems to have favorable characteristics for streaming and a 
> distributed implementation, and there is a python implementation for 
> reference.
> It is a fairly standalone piece, and in that respect available to people who 
> don't know too much about spark internals.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org

Reply via email to