same 30,000 documents, same queries; only the dense_vector index_options.type differs (the first row is Spring AI's own mapping)
type          recall@10    p50 ms  filt recall    filt p50 ms      store
bbq_hnsw*         0.491       3.6        0.544            3.0     54.4mb
int8_hnsw         0.952       3.0        0.974            3.1     64.1mb
hnsw              0.995       3.0        1.000            2.7     52.6mb
* default; its full mapping is in 04-defaults-that-matter.txt