[jira] [Created] (LUCENE-6645) BKD tree queries should use BitDocIdSet.Builder

["Michael McCandless (JIRA)" <ji...@apache.org>]

Michael McCandless created LUCENE-6645:
------------------------------------------

             Summary: BKD tree queries should use BitDocIdSet.Builder
                 Key: LUCENE-6645
                 URL: https://issues.apache.org/jira/browse/LUCENE-6645
             Project: Lucene - Core
          Issue Type: Improvement
            Reporter: Michael McCandless


When I was iterating on BKD tree originally I remember trying to use this builder (which makes a sparse bit set at first and then upgrades to dense if enough bits get set) and being disappointed with its performance.

I wound up just making a FixedBitSet every time, but this is obviously wasteful for small queries.

It could be the perf was poor because I was always .or'ing in DISIs that had 512 - 1024 hits each time (the size of each leaf cell in the BKD tree)?  I also had to make my own DISI wrapper around each leaf cell... maybe that was the source of the slowness, not sure.

I also sort of wondered whether the SmallDocSet in spatial module (backed by a SentinelIntSet) might be faster ... though it'd need to be sorted in the and after building before returning to Lucene.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org