[ 
https://issues.apache.org/jira/browse/LUCENE-5721?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Adrien Grand resolved LUCENE-5721.
----------------------------------

    Resolution: Fixed

> Monotonic packed could maybe be faster
> --------------------------------------
>
>                 Key: LUCENE-5721
>                 URL: https://issues.apache.org/jira/browse/LUCENE-5721
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Robert Muir
>            Assignee: Adrien Grand
>         Attachments: LUCENE-5703.patch
>
>
> This compression is used in lucene for monotonically increasing offsets, e.g. 
> stored fields index, dv BINARY/SORTED_SET offsets, OrdinalMap (used for 
> merging and faceting dv) and so on.
> Today this stores a +/- deviation from an expected line of y=mx + b, where b 
> is the minValue for the block and m is the average delta from the previous 
> value. Because it can be negative, we have to do some additional work to 
> zigzag-decode.
> Can we just instead waste a bit for every value explicitly (lower the 
> minValue by the min delta) so that deltas are always positive and we can have 
> a simpler decode? Maybe If we do this, the new guy should assert that values 
> are actually monotic at write-time. The current one supports "mostly monotic" 
> but do we really need that flexibility anywhere? If so it could always be 
> kept...



--
This message was sent by Atlassian JIRA
(v6.2#6252)

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

Reply via email to