[ 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