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Robert Muir commented on LUCENE-4571: ------------------------------------- I like the ideas Stefan! {quote} Using BooleanScorer will probably only give improvement by a factor (in some cases), but also this scorers would still generate all these useless candidates. {quote} It might be hard to beat this one (which already supports minShouldMatch as a side effect of its coord computation anyway i think) in cases with lots of terms because I feel like inevitably supporting advance() on the subscorers will result in more heap operations/cpu (at least when i messed around on paper it seemed this way). In fact in some situations I think even this one should be used when there are mandatory clauses: in any case booleanweight should have better heuristics to decide, limited by what the collector can deal with. Collectors that support out of order scoring today I think are likely a lot faster with these minShouldMatch types of queries than BooleanScorer2. Thats why i brought it up: it could be an easy win for e.g. solr users. But when the number of terms is smallish and one is super-common, its silly we don't try to improve the BS2 impl to at least try to handle the worst case :) At least for the sake of simplicity (not necessarily performance) I still think it would be good to factor minshouldmatch behavior out of disjunctionsumscorer if we try to make it use advance() on subscorers. > speedup disjunction with minShouldMatch > ---------------------------------------- > > Key: LUCENE-4571 > URL: https://issues.apache.org/jira/browse/LUCENE-4571 > Project: Lucene - Core > Issue Type: Improvement > Components: core/search > Affects Versions: 4.1 > Reporter: Mikhail Khludnev > > even minShouldMatch is supplied to DisjunctionSumScorer it enumerates whole > disjunction, and verifies minShouldMatch condition [on every > doc|https://github.com/apache/lucene-solr/blob/trunk/lucene/core/src/java/org/apache/lucene/search/DisjunctionSumScorer.java#L70]: > {code} > public int nextDoc() throws IOException { > assert doc != NO_MORE_DOCS; > while(true) { > while (subScorers[0].docID() == doc) { > if (subScorers[0].nextDoc() != NO_MORE_DOCS) { > heapAdjust(0); > } else { > heapRemoveRoot(); > if (numScorers < minimumNrMatchers) { > return doc = NO_MORE_DOCS; > } > } > } > afterNext(); > if (nrMatchers >= minimumNrMatchers) { > break; > } > } > > return doc; > } > {code} > [~spo] proposes (as well as I get it) to pop nrMatchers-1 scorers from the > heap first, and then push them back advancing behind that top doc. For me the > question no.1 is there a performance test for minShouldMatch constrained > disjunction. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators 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