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https://issues.apache.org/jira/browse/LUCENE-4481?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13480428#comment-13480428
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Dawid Weiss commented on LUCENE-4481:
-------------------------------------

I've been following the discussion but I  don't get the original problem -- 
could you provide an example of a token sequence (graph) for which the problem 
occurs? Is it in the patch somewhere (I looked at it but missed it somehow)?
                
> AnalyzingSuggester may fail to return correct topN suggestions
> --------------------------------------------------------------
>
>                 Key: LUCENE-4481
>                 URL: https://issues.apache.org/jira/browse/LUCENE-4481
>             Project: Lucene - Core
>          Issue Type: Bug
>            Reporter: Michael McCandless
>            Assignee: Michael McCandless
>             Fix For: 4.1, 5.0
>
>         Attachments: LUCENE-4481.patch, LUCENE-4481.patch, LUCENE-4481.patch, 
> LUCENE-4481.patch
>
>
> I hit this when working on LUCENE-4480.
> Because AnalyzingSuggester may prune some of the topN paths found by FST's 
> Util.TopNSearcher, this means the queue size limit of topN makes the overall 
> search inadmissible, ie it may incorrectly prune paths that would have lead 
> to a competitive path.
> However, such pruning is rare: it happens only for graph token streams, and 
> even then only when competitive analyzed forms share the same surface forms.
> The simplest way to fix this is to make the queue unbounded but this is 
> likely a sizable performance hit ... I haven't tested yet.  It's even 
> possible the way the dups happen (always at the "end" of the suggestion, 
> because we tack on 0 byte followed by ord dedup byte) prevent this bug from 
> even occurring and so this could all be a false alarm!  I have to try to make 
> a test case showing it ...
> A cop-out solution would be to expose a separate queueSize or queueMultiplier 
> (over the topN) so that if users are affected by this they could crank up the 
> queue size or multiplier.

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