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Michael Busch commented on LUCENE-3328: --------------------------------------- {quote} The ConjunctionTermScorer sorts the DocsEnums by their frequency in the ctor. The leader will always be the lowest frequent term in the set. is this what you mean here? {quote} Cool, yeah that's roughly what I meant. In general, it's best to always pick the lowest-df enum as leader: 1) after initialization 2) after a hit was found 3) whenever a doc matched m out of n enums, 1 < m < n I think what you described covers situation 1), does it also cover 2) and 3)? > Specialize BooleanQuery if all clauses are TermQueries > ------------------------------------------------------ > > Key: LUCENE-3328 > URL: https://issues.apache.org/jira/browse/LUCENE-3328 > Project: Lucene - Java > Issue Type: Improvement > Components: core/search > Affects Versions: 3.4, 4.0 > Reporter: Simon Willnauer > Fix For: 4.0 > > Attachments: LUCENE-3328.patch, LUCENE-3328.patch, LUCENE-3328.patch > > > During work on LUCENE-3319 I ran into issues with BooleanQuery compared to > PhraseQuery in the exact case. If I disable scoring on PhraseQuery and bypass > the position matching, essentially doing a conjunction match, > ExactPhraseScorer beats plain boolean scorer by 40% which is a sizeable gain. > I converted a ConjunctionScorer to use DocsEnum directly but still didn't get > all the 40% from PhraseQuery. Yet, it turned out with further optimizations > this gets very close to PhraseQuery. The biggest gain here came from > converting the hand crafted loop in ConjunctionScorer#doNext to a for loop > which seems to be less confusing to hotspot. In this particular case I think > code specialization makes lots of sense since BQ with TQ is by far one of the > most common queries. > I will upload a patch shortly -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org