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https://issues.apache.org/jira/browse/LUCENE-10225?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17445043#comment-17445043
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ASF subversion and git services commented on LUCENE-10225:
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Commit c71cbac4f9d6a56942625405fd78256733017fd8 in lucene's branch
refs/heads/main from Bruno Roustant
[ https://gitbox.apache.org/repos/asf?p=lucene.git;h=c71cbac4f ]
LUCENE-10225: Improve IntroSelector with 3-way partitioning.
> Improve IntroSelector with 3-way partitioning
> ---------------------------------------------
>
> Key: LUCENE-10225
> URL: https://issues.apache.org/jira/browse/LUCENE-10225
> Project: Lucene - Core
> Issue Type: Improvement
> Reporter: Bruno Roustant
> Priority: Major
> Time Spent: 3h 20m
> Remaining Estimate: 0h
>
> The same way we improved IntroSorter, we can improve IntroSelector with
> Bentley-McIlroy 3-way partitioning. The gain in performance is roughly the
> same.
> With this new approach, we always use medians-of-medians (Tukey's Ninther),
> so there is no real gain to fallback to a slower medians-of-medians technique
> as an introspective protection (like the existing implementation does).
> Instead we can simply shuffle the sub-range if we exceed the recursive max
> depth (this does not change the speed as this intro-protective mechanism
> almost never happens - maybe only in adversarial cases).
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