lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Mark Harwood (JIRA)" <>
Subject [jira] [Commented] (LUCENE-4069) Segment-level Bloom filters for a 2 x speed up on rare term searches
Date Mon, 18 Jun 2012 12:25:46 GMT


Mark Harwood commented on LUCENE-4069:

bq. I think the fix is simple: you are not overriding Terms.intersect now, in BloomFilteredTerms

Good catch - a quick test indeed shows a speed up on fuzzy queries. 
I'll prepare a new patch.

I'm not sure on why 3.6+Bloom is faster than 4+Bloom in my tests. I'll take a closer look
at your benchmark.
> Segment-level Bloom filters for a 2 x speed up on rare term searches
> --------------------------------------------------------------------
>                 Key: LUCENE-4069
>                 URL:
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: core/index
>    Affects Versions: 3.6, 4.0
>            Reporter: Mark Harwood
>            Priority: Minor
>             Fix For: 4.0, 3.6.1
>         Attachments: BloomFilterPostingsBranch4x.patch, MHBloomFilterOn3.6Branch.patch,
> An addition to each segment which stores a Bloom filter for selected fields in order
to give fast-fail to term searches, helping avoid wasted disk access.
> Best suited for low-frequency fields e.g. primary keys on big indexes with many segments
but also speeds up general searching in my tests.
> Overview slideshow here:
> Benchmarks based on Wikipedia content here:
> Patch based on 3.6 codebase attached.
> There are no 3.6 API changes currently - to play just add a field with "_blm" on the
end of the name to invoke special indexing/querying capability. Clearly a new Field or schema
declaration(!) would need adding to APIs to configure the service properly.
> Also, a patch for Lucene4.0 codebase introducing a new PostingsFormat

This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:!default.jspa
For more information on JIRA, see:


To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message