Which session parameter tunes the recall/latency trade-off for HNSW at query time?
- A ivfflat.probes
- B hnsw.ef_search (correct answer)
- C work_mem
- D random_page_cost
Shortcut: ef_search controls how many candidates are examined per query. Higher values improve recall at the cost of latency, and can be set per session or per transaction.
SET hnsw.ef_search controls how many candidates are examined per query. Higher values improve recall at the cost of latency, and can be set per session or per transaction.