[ 
https://issues.apache.org/jira/browse/ARROW-8543?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

ASF GitHub Bot updated ARROW-8543:
----------------------------------
    Labels: pull-request-available  (was: )

> [C++] IO: single pass coalescing algorithm
> ------------------------------------------
>
>                 Key: ARROW-8543
>                 URL: https://issues.apache.org/jira/browse/ARROW-8543
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++
>            Reporter: Mayur Srivastava
>            Priority: Major
>              Labels: pull-request-available
>
> The current coalescing algorithm is a O(N^2) two pass algorithm (where N is 
> number of ranges) (first implemented in 
> https://issues.apache.org/jira/browse/ARROW-7995). In the first pass, the 
> Coalesce() function finds the begin and end of a candidate range that can be 
> coalesced. In the second, pass the CoalesceUntilLargeEnough() function goes 
> over the ranges from begin to end and adds coalesced range to the result 
> (out).
> The proposal is to convert the algorithm to an O(N) single pass algorithm 
> that computes coalesced ranges while making the first pass over the ranges in 
> the list. This algorithm is also shorter in lines of code and hence 
> (hopefully) more maintainable in long term.
>  



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Reply via email to