lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Yonik Seeley (JIRA)" <j...@apache.org>
Subject [jira] Commented: (LUCENE-2531) FieldComparator.TermOrdValComparator compares by value unnecessarily
Date Sun, 11 Jul 2010 00:10:50 GMT

    [ https://issues.apache.org/jira/browse/LUCENE-2531?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12887122#action_12887122
] 

Yonik Seeley commented on LUCENE-2531:
--------------------------------------

The thing that jumps out at me is the removal of "reversed"... I'd need to apply the patch
to study enough to figure that out, but any clues you could give would be helpful (yes, I'm
being lazy ;-)

> FieldComparator.TermOrdValComparator compares by value unnecessarily
> --------------------------------------------------------------------
>
>                 Key: LUCENE-2531
>                 URL: https://issues.apache.org/jira/browse/LUCENE-2531
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Search
>            Reporter: Michael McCandless
>            Priority: Minor
>             Fix For: 3.1, 4.0
>
>         Attachments: LUCENE-2504-3x.patch, LUCENE-2504.patch, LUCENE-2531-3x.patch, LUCENE-2531.patch
>
>
> Digging on LUCENE-2504, I noticed that TermOrdValComparator's compareBottom method falls
back on compare-by-value when it needn't.
> Specifically, if we know the current bottom ord "matches" the current segment, we can
skip the value comparison when the ords are the same (ie, return 0) because the ords are exactly
comparable.
> This is hurting string sort perf especially for optimized indices (and also unoptimized
indices), and especially for highly redundant (not many unique values) fields.  This affects
all releases >= 2.9.x, but trunk is likely more severely affected since looking up a value
is more costly.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org


Mime
View raw message