numpy exact                      p50=  7.15ms p95=  7.56ms recall@10=1.000
load 100000 rows: 3.4s
table size: 157 MB
pgvector seq scan, workers=0     p50= 37.22ms p95= 39.95ms recall@10=1.000
pgvector seq scan, workers=2     p50= 37.98ms p95= 39.66ms recall@10=1.000
HNSW build (m=16, efc=64): 30.7s; index size: 195 MB
pgvector HNSW ef_search=10       p50=  0.67ms p95=  1.05ms recall@10=0.613
pgvector HNSW ef_search=40       p50=  0.99ms p95=  1.72ms recall@10=0.955
pgvector HNSW ef_search=100      p50=  1.90ms p95=  2.47ms recall@10=0.985
pgvector HNSW ef_search=200      p50=  3.50ms p95=  4.26ms recall@10=1.000