[ 
https://issues.apache.org/jira/browse/LUCENE-1476?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12665748#action_12665748
 ] 

Paul Elschot commented on LUCENE-1476:
--------------------------------------

>>> If we move the deletions filtering up, then we'd increase traffic through
>>> that cache
>>
>> OK, right. So we may have some added cost because of this. I think it's only
>> TermScorer that uses the bulk API though.

>The original BooleanScorer also pre-fetches. (That doesn't affect KS because
> ORScorer, ANDScorer, NOTScorer and RequiredOptionScorer (which have
> collectively replaced BooleanScorer) all proceed doc-at-a-time and implement
> skipping.)

For OR like queries, that use Scorer.next(), deletions might be treated as early
as possible, since each hit will cause a matching doc and a corresponding score 
calculation.

For AND like queries, that use Scorer.skipTo(), deletions can be treated later,
for example in skipTo() of the conjunction/and/scorer.

In the same way, prefetching into a larger term documents buffer helps for OR 
queries,
but gets in the way for AND queries.


> BitVector implement DocIdSet, IndexReader returns DocIdSet deleted docs
> -----------------------------------------------------------------------
>
>                 Key: LUCENE-1476
>                 URL: https://issues.apache.org/jira/browse/LUCENE-1476
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Index
>    Affects Versions: 2.4
>            Reporter: Jason Rutherglen
>            Priority: Trivial
>         Attachments: LUCENE-1476.patch, LUCENE-1476.patch, 
> quasi_iterator_deletions.diff, quasi_iterator_deletions_r2.diff
>
>   Original Estimate: 12h
>  Remaining Estimate: 12h
>
> Update BitVector to implement DocIdSet.  Expose deleted docs DocIdSet from 
> IndexReader.

-- 
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: java-dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: java-dev-h...@lucene.apache.org

Reply via email to