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https://issues.apache.org/jira/browse/LUCENE-4069?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13284520#comment-13284520
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Simon Willnauer commented on LUCENE-4069:
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hey mark, this looks very interesting. I wonder if that also helps indexing in
terms of applying deletes. did you test that at all or is that something are
looking into as well? For deletes this could be very handy since bloom filters
should help a lot when a given key is likely to only in one segment.
Regarding the code, I think BloomFilter should be like Pulsing and only be a
PostingsFormat. You should make the BloomFilterPostingsFormat abstract and pass
in the "wrapped" postings format and delegate independent of the field.
PostingsFormat is per field and is resolved by the codec. An actual
implementation should subclass the abstract BloomFilterPostingsFormat that way
you have a fixed PostingsFormat per "delegate" and don't need to deal with
"which field got which delegate" bla bla.
We should not have a Bloomfilter codec but rather swap in the bloomfilter
postings format in test via random codec. I also wonder if we can extract a
"bloomfilter" class into utils that builds an BloomFilter this could be useful
elsewhere.
> Segment-level Bloom filters for a 2 x speed up on rare term searches
> --------------------------------------------------------------------
>
> Key: LUCENE-4069
> URL: https://issues.apache.org/jira/browse/LUCENE-4069
> Project: Lucene - Java
> Issue Type: Improvement
> Components: core/index
> Affects Versions: 3.6
> Reporter: Mark Harwood
> Priority: Minor
> Fix For: 3.6.1
>
> Attachments: BloomFilterCodec40.patch,
> MHBloomFilterOn3.6Branch.patch, PrimaryKey40PerformanceTestSrc.zip
>
>
> 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:
> http://www.slideshare.net/MarkHarwood/lucene-bloomfilteredsegments
> Benchmarks based on Wikipedia content here: http://goo.gl/X7QqU
> Patch based on 3.6 codebase attached.
> There are no 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.
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