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Michael McCandless commented on LUCENE-9536: -------------------------------------------- {quote}Thanks [~jtibshirani]! {quote} ++ > Optimize OrdinalMap when one segment contains all distinct values? > ------------------------------------------------------------------ > > Key: LUCENE-9536 > URL: https://issues.apache.org/jira/browse/LUCENE-9536 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Julie Tibshirani > Priority: Minor > Fix For: 8.8 > > Time Spent: 3h > Remaining Estimate: 0h > > For doc values that are not too high cardinality, it seems common to have > some large segments that contain all distinct values (plus many small > segments who are missing some values). In this case, we could check if the > first segment ords map perfectly to global ords and if so store > `globalOrdDeltas` and `firstSegments` as `LongValues.ZEROES`. This could save > a small amount of space. > I don’t think it would help a huge amount, especially since the optimization > might only kick in with small/ medium cardinalities, which don’t create huge > `OrdinalMap` instances anyways? But it is simple and seemed worth mentioning. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org