[LUCENE-10367] Use WANDScorer in CoveringQuery Can accelerate scorer time

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 9.1
• Component/s: core/query/scoring, core/search, modules/sandbox
• Lucene Fields: New
• Review Patch?: Yes
• Assignee: Unassigned
• Reporter: LuYunCheng
• Created: 10/Jan/22 12:53
• Updated: 28/Aug/22 16:34
• Resolved: 08/Feb/22 16:39

Description

When using CoveringQuery In Elasticsearch with terms_set query, it takes too much time in CoveringScore and major cost in matain the DisiPriorityQueue: subScorers.

But when minimumNumberMatch is ConstantLongValuesSource, we can use WANDScorer to optimize it.

 

i do a mini benchmark with 1m docs, which code in LUCENE-10367.patch TestCoveringQuery.java  testRandomBench()

it shows: 

TEST: WAND elapsed 67ms
TEST: NOWAND elapsed 163ms

My testing environment is macBook with Intel Core i7 16GMem.