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https://issues.apache.org/jira/browse/LUCENE-7526?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15668354#comment-15668354
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ASF subversion and git services commented on LUCENE-7526:
---------------------------------------------------------

Commit 7af454ad767c3a0364757d6fcf55bff9f063febe in lucene-solr's branch 
refs/heads/master from [~dsmiley]
[ https://git-wip-us.apache.org/repos/asf?p=lucene-solr.git;h=7af454a ]

LUCENE-7526: UnifiedHighlighter: enhance MTQ passage relevancy. 
TokenStreamFromTermVector isn't used by the UH anymore. Refactor 
AnalysisOffsetStrategy into TokenStream and MemoryIndex strategies, and related 
refactorings from that.


> Improvements to UnifiedHighlighter OffsetStrategies
> ---------------------------------------------------
>
>                 Key: LUCENE-7526
>                 URL: https://issues.apache.org/jira/browse/LUCENE-7526
>             Project: Lucene - Core
>          Issue Type: Improvement
>          Components: modules/highlighter
>            Reporter: Timothy M. Rodriguez
>            Assignee: David Smiley
>            Priority: Minor
>             Fix For: 6.4
>
>         Attachments: LUCENE-7526.patch
>
>
> This ticket improves several of the UnifiedHighlighter FieldOffsetStrategies 
> by reducing reliance on creating or re-creating TokenStreams.
> The primary changes are as follows:
> * AnalysisOffsetStrategy - split into two offset strategies
>   ** MemoryIndexOffsetStrategy - the primary analysis mode that utilizes a 
> MemoryIndex for producing Offsets
>   ** TokenStreamOffsetStrategy - an offset strategy that avoids creating a 
> MemoryIndex.  Can only be used if the query distills down to terms and 
> automata.
> * TokenStream removal 
>   ** MemoryIndexOffsetStrategy - previously a TokenStream was created to fill 
> the memory index and then once consumed a new one was generated by 
> uninverting the MemoryIndex back into a TokenStream if there were automata 
> (wildcard/mtq queries) involved.  Now this is avoided, which should save 
> memory and avoid a second pass over the data.
>   ** TermVectorOffsetStrategy - this was refactored in a similar way to avoid 
> generating a TokenStream if automata are involved.
>   ** PostingsWithTermVectorsOffsetStrategy - similar refactoring
> * CompositePostingsEnum - aggregates several underlying PostingsEnums for 
> wildcard/mtq queries.  This should improve relevancy by providing unified 
> metrics for a wildcard across all it's term matches
> * Added a HighlightFlag for enabling the newly separated 
> TokenStreamOffsetStrategy since it can adversely affect passage relevancy



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