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Michael McCandless commented on LUCENE-5879: -------------------------------------------- Hmm, one problem here is ... with this patch we are inserting auto-prefix terms for numeric fields which is sort of silly (prefix terms of prefix terms). Not sure if/how to prevent that... I guess we could do something hacky and try to detect when writing the postings that it's a numeric field ... hmm. I removed the DEBUG nocommits and ran a trunk vs patch perf test on all English wikipedia "medium" docs (33.3M) and it didn't look like there was any real change, just noise. > Add auto-prefix terms to block tree terms dict > ---------------------------------------------- > > Key: LUCENE-5879 > URL: https://issues.apache.org/jira/browse/LUCENE-5879 > Project: Lucene - Core > Issue Type: New Feature > Components: core/codecs > Reporter: Michael McCandless > Assignee: Michael McCandless > Fix For: 4.10, 5.0 > > Attachments: LUCENE-5879.patch, LUCENE-5879.patch, LUCENE-5879.patch, > LUCENE-5879.patch, LUCENE-5879.patch > > > This cool idea to generalize numeric/trie fields came from Adrien: > Today, when we index a numeric field (LongField, etc.) we pre-compute > (via NumericTokenStream) outside of indexer/codec which prefix terms > should be indexed. > But this can be inefficient: you set a static precisionStep, and > always add those prefix terms regardless of how the terms in the field > are actually distributed. Yet typically in real world applications > the terms have a non-random distribution. > So, it should be better if instead the terms dict decides where it > makes sense to insert prefix terms, based on how dense the terms are > in each region of term space. > This way we can speed up query time for both term (e.g. infix > suggester) and numeric ranges, and it should let us use less index > space and get faster range queries. > > This would also mean that min/maxTerm for a numeric field would now be > correct, vs today where the externally computed prefix terms are > placed after the full precision terms, causing hairy code like > NumericUtils.getMaxInt/Long. So optos like LUCENE-5860 become > feasible. > The terms dict can also do tricks not possible if you must live on top > of its APIs, e.g. to handle the adversary/over-constrained case when a > given prefix has too many terms following it but finer prefixes > have too few (what block tree calls "floor term blocks"). -- 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