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Robert Muir commented on LUCENE-3234: ------------------------------------- You can change it if you don't mind. However, I think I agree it would be good to figure out if there is an n^2 here. This might have some affect on what the default value should be... ideally there is some way we could fix the n^2. Is there a way to turn your test case into a benchmark, or do you have a separate benchmark (the example you mentioned where it blows up really bad). This could help in looking at what's going on. > Provide limit on phrase analysis in FastVectorHighlighter > --------------------------------------------------------- > > Key: LUCENE-3234 > URL: https://issues.apache.org/jira/browse/LUCENE-3234 > Project: Lucene - Java > Issue Type: Improvement > Reporter: Mike Sokolov > Attachments: LUCENE-3234.patch > > > With larger documents, FVH can spend a lot of time trying to find the > best-scoring snippet as it examines every possible phrase formed from > matching terms in the document. If one is willing to accept > less-than-perfect scoring by limiting the number of phrases that are > examined, substantial speedups are possible. This is analogous to the > Highlighter limit on the number of characters to analyze. > The patch includes an artifical test case that shows > 1000x speedup. In a > more normal test environment, with English documents and random queries, I am > seeing speedups of around 3-10x when setting phraseLimit=1, which has the > effect of selecting the first possible snippet in the document. Most of our > sites operate in this way (just show the first snippet), so this would be a > big win for us. > With phraseLimit = -1, you get the existing FVH behavior. At larger values of > phraseLimit, you may not get substantial speedup in the normal case, but you > do get the benefit of protection against blow-up in pathological cases. -- 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