Fix 'too many LWLocks taken' error when scanning hypertables#167
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tjgreen42 merged 3 commits intorelease/0.4.1from Jan 23, 2026
Merged
Fix 'too many LWLocks taken' error when scanning hypertables#167tjgreen42 merged 3 commits intorelease/0.4.1from
tjgreen42 merged 3 commits intorelease/0.4.1from
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Release the per-index LWLock after tp_memtable_search() completes in tp_execute_scoring_query(). The lock was being acquired but never released, causing locks to accumulate when querying hypertables with many chunks (e.g., 587 chunks). This is the scan-path equivalent of the build-path fix in b7f6539.
The lock upgrade warning no longer occurs because we release the per-index lock after tp_memtable_search() completes.
tjgreen42
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Jan 22, 2026
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Trivial change to trigger CI
Signed-off-by: Todd J. Green <tj@timescale.com>
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Summary
Fixes "too many LWLocks taken" error when querying BM25 indexes on hypertables with many chunks.
Problem
When scanning a hypertable with many chunks (e.g., 587), each chunk's BM25 index scan acquires a per-index LWLock but never releases it until transaction end, exceeding Postgres's ~200 lock limit.
Solution
Release the lock immediately after
tp_memtable_search()returns, since we've already extracted all CTIDs into memory.This is the scan-path equivalent of the build-path fix in b7f6539.
Testing