Formal models and scripts: reqexcl-bulkscorer-excluded-run-skip-16669

Tools: Python

These are the working models and scripts this part of the hunt used. Some encode the code as it is (a counterexample is the expected result), others a fixed or correct variant; read the header comment of each file. Paths inside them were replaced by placeholders such as $LUCENE (a Lucene checkout) and $WORK.

Findings

• Since #16669 (10.6.0 and main), ReqExclBulkScorer no longer skips long runs of excluded doc IDs: for +R -X it scores the required clause in every 4096-doc window, even windows X fully excludes, so R's iterator steps through all of its matches inside X's runs (10,001 moves for 1,000 hits in a 10,000-doc segment, where 10.0.0-10.5.2 need 1,001; performance regression, results correct) (finding LFV-1044; repro · finding page)

Files

• reqexcl-bulkscorer-excluded-run-skip-lost-16669/model/ReqExclCostModel.py (used for LFV-1044)

How to run

• Python: python3 <file>.py; scripts that import z3 need the z3-solver package.

Snapshot of 2026-11-03. AI-assisted; not yet triaged by a human Lucene committer. Feedback: open an issue in lucene-ai-bug-hunt.