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Yuriy commented on LUCENE-5052: ------------------------------- This is very simple implementation of codec which stores PostingLists as BitSets. This implementation passes BasePostingsFormatTestCase.testDocsOnly() test. Also I have found difficult to implement term dictionary and feel like it's better to somehow combine this posting format with any of standard ones. > bitset codec for off heap filters > --------------------------------- > > Key: LUCENE-5052 > URL: https://issues.apache.org/jira/browse/LUCENE-5052 > Project: Lucene - Core > Issue Type: New Feature > Components: core/codecs > Reporter: Mikhail Khludnev > Labels: features > Fix For: 5.0 > > > Colleagues, > When we filter we don’t care any of scoring factors i.e. norms, positions, > tf, but it should be fast. The obvious way to handle this is to decode > postings list and cache it in heap (CachingWrappingFilter, Solr’s DocSet). > Both of consuming a heap and decoding as well are expensive. > Let’s write a posting list as a bitset, if df is greater than segment's > maxdocs/8 (what about skiplists? and overall performance?). > Beside of the codec implementation, the trickiest part to me is to design API > for this. How we can let the app know that a term query don’t need to be > cached in heap, but can be held as an mmaped bitset? > WDYT? -- This message was sent by Atlassian JIRA (v6.1#6144) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org