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Michael McCandless commented on LUCENE-6890: -------------------------------------------- bq. you've mentioned that you wanted to uploaded the patch anyway but it seems to be missing. Gak, you're right! Thanks for noticing, I would have rm'd this checkout soon! > Specialize 1D dimensional values intersection > --------------------------------------------- > > Key: LUCENE-6890 > URL: https://issues.apache.org/jira/browse/LUCENE-6890 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Michael McCandless > > I tried implementing the same specialization we had before LUCENE-6881 for > the 1D case, but after testing it, I don't think it's worth it. > I'll upload the patch here for posterity (tests pass), but net/net it adds > non-trivial code complexity in exchange for minor (5.39 sec -> 5.25 sec for > 225 queries) query gains. Maybe in the future someone could improve this so > it's more compelling... but I don't think the tradeoff is worth it today. > Furthermore, the optimization 1) requires an API change, and 2) is not even > admissible in the current patch, since the query could be a union of multiple > disjoint ranges when the optimization assumes it's just a single range. > The gist of the idea is to locate the start leaf block and end leaf block, > make an informed estimate of the expected result set size, and then do a > linear scan of the leaf blocks, vs the recursion and "grow per leaf block" we > do today. I think the conclusion is that this used to be more sizable win, > but {{DocIdSetBuilder}} has improved so that it is plenty fast without > "upfront" growing, which is nice :) > Or maybe my benchmark is bogus ;) > I'll commit the minor code comment / TODOs / test improvements from the patch > ... -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org