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Adrien Grand commented on LUCENE-3892: -------------------------------------- The comment you added in 1371011 on the value of {{BLOCK_SIZE}} caught my attention: I think that BLOCK_SIZE should be at least 64 with PackedInts encoding/decoding since these conversions are long-aligned (I backported your two commits and added a comment about this). For example, the {{PACKED}} 7-bits encoder cannot encode less than 64 values in one iteration. In case someone would really want to use smaller block sizes (eg. 32), I think it should still perform pretty well if {{acceptableOverheadRatio >= ~25%}} (in that case, all bits-per-value in the [1-24] range either use a {{PACKED_SINGLE_BLOCK}} encoder or an 8-bits, 16-bits or 24-bits {{PACKED}} decoder). Do we plan to make the block size configurable? > Add a useful intblock postings format (eg, FOR, PFOR, PFORDelta, > Simple9/16/64, etc.) > ------------------------------------------------------------------------------------- > > Key: LUCENE-3892 > URL: https://issues.apache.org/jira/browse/LUCENE-3892 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Michael McCandless > Labels: gsoc2012, lucene-gsoc-12 > Fix For: 4.1 > > Attachments: LUCENE-3892-BlockTermScorer.patch, > LUCENE-3892-blockFor&hardcode(base).patch, > LUCENE-3892-blockFor&packedecoder(comp).patch, > LUCENE-3892-blockFor-with-packedints-decoder.patch, > LUCENE-3892-blockFor-with-packedints-decoder.patch, > LUCENE-3892-blockFor-with-packedints.patch, LUCENE-3892-bulkVInt.patch, > LUCENE-3892-direct-IntBuffer.patch, LUCENE-3892-for&pfor-with-javadoc.patch, > LUCENE-3892-handle_open_files.patch, LUCENE-3892-non-specialized.patch, > LUCENE-3892-pfor-compress-iterate-numbits.patch, > LUCENE-3892-pfor-compress-slow-estimate.patch, LUCENE-3892_for_byte[].patch, > LUCENE-3892_for_int[].patch, LUCENE-3892_for_unfold_method.patch, > LUCENE-3892_pfor_unfold_method.patch, LUCENE-3892_pulsing_support.patch, > LUCENE-3892_settings.patch, LUCENE-3892_settings.patch > > > On the flex branch we explored a number of possible intblock > encodings, but for whatever reason never brought them to completion. > There are still a number of issues opened with patches in different > states. > Initial results (based on prototype) were excellent (see > http://blog.mikemccandless.com/2010/08/lucene-performance-with-pfordelta-codec.html > ). > I think this would make a good GSoC project. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org