# khive-retrieval: Benchmark Ledger
## Suite inventory
| `benches/fusion_bench.rs` | `fuse/rrf` | input sizes 50 / 100 / 250 / 500 | `fuse_search_results` with RRF strategy |
| `benches/fusion_bench.rs` | `fuse/weighted` | input sizes 50 / 100 / 250 / 500 | `fuse_search_results` with weighted strategy |
| `benches/fusion_bench.rs` | `fuse/union` | input sizes 50 / 100 / 250 / 500 | `fuse_search_results` with union strategy |
| `benches/fusion_bench.rs` | `fuse/three_sources` | input sizes 50 / 200 / 500 | three-source RRF fusion |
| `benches/fusion_bench.rs` | `hybrid_config` | new / builder_rrf / builder_weighted | `HybridConfig` construction and builder chains |
| `benches/fusion_bench.rs` | `config/search` | default / preset_vector_only / preset_keyword_only | `SearchConfig` construction |
| `benches/fusion_bench.rs` | `policy` | by_policy / by_predicate | policy filtering over 1000-item result sets |
| `benches/fusion_bench.rs` | `eval` | compute_all_100 / compute_all_1000 | retrieval eval metric computation |
## Run command
```sh
cargo bench --manifest-path crates/khive-retrieval/Cargo.toml --bench fusion_bench
```
HTML reports are written to `target/criterion/`.
## Environment notes
- Benchmarks use Criterion 0.5 with `html_reports` feature.
- `fuse/rrf`, `fuse/weighted`, `fuse/union`, and `hybrid_config` use `sample_size(200)`.
- `fuse/three_sources` uses `sample_size(100)`.
- Results depend on CPU micro-architecture (branch predictor, cache sizes). Record machine for cross-run comparisons.
- Clone / allocation setup inside `b.iter` is a known methodology issue (see AUD-005 in the 2026-06-06 audit). Results for `fuse/*` groups currently include vector-clone cost alongside fusion cost. Baseline entries below reflect current methodology until AUD-005 is resolved.
## Baseline (2026-06-06, post-sweep)
**Toolchain:** rustc 1.94.1 (e408947bf 2026-03-25)
**Machine:** arm64 (Apple Silicon), macOS Darwin 25.5.0
### Fusion (2-source)
| fuse/rrf/50 | 7.577 µs | 7.818 µs | 8.127 µs | 37/200 (19%) |
| fuse/rrf/100 | 15.14 µs | 15.35 µs | 15.60 µs | 30/200 (15%) |
| fuse/rrf/250 | 38.38 µs | 39.08 µs | 39.87 µs | 17/200 (9%) |
| fuse/rrf/500 | 91.68 µs | 95.74 µs | 100.75 µs | 18/200 (9%) |
| fuse/weighted/50 | 7.806 µs | 8.313 µs | 8.902 µs | 6/200 (3%) |
| fuse/weighted/100| 11.72 µs | 11.99 µs | 12.38 µs | 26/200 (13%) |
| fuse/weighted/250| 29.02 µs | 29.10 µs | 29.17 µs | 9/200 (5%) |
| fuse/weighted/500| 60.90 µs | 63.63 µs | 66.76 µs | 16/200 (8%) |
| fuse/union/50 | 3.517 µs | 3.644 µs | 3.793 µs | 25/200 (13%) |
| fuse/union/100 | 7.218 µs | 7.243 µs | 7.272 µs | 18/200 (9%) |
| fuse/union/250 | 18.93 µs | 19.11 µs | 19.34 µs | 21/200 (11%) |
| fuse/union/500 | 39.11 µs | 39.62 µs | 40.28 µs | 26/200 (13%) |
### Fusion (3-source)
| fuse/three_sources/50 | 10.78 µs | 10.90 µs | 11.07 µs | 13/100 (13%) |
| fuse/three_sources/200| 42.84 µs | 43.54 µs | 44.48 µs | 8/100 (8%) |
| fuse/three_sources/500| 107.8 µs | 110.7 µs | 115.2 µs | 13/100 (13%) |
### Config Construction
| hybrid_config/new | 3.685 ns | 3.750 ns | 3.827 ns | 15/200 (8%) |
| hybrid_config/builder_rrf | 6.151 ns | 6.342 ns | 6.586 ns | 15/200 (8%) |
| hybrid_config/builder_weighted | 21.87 ns | 22.30 ns | 22.86 ns | 9/200 (5%) |
| hybrid_config/normalized_weights| 843.4 ps | 877.9 ps | 915.4 ps | 12/200 (6%) |
| search_config/default | 3.631 ns | 3.750 ns | 3.896 ns | 12/200 (6%) |
## Regression notes
- A regression is flagged when Criterion reports a statistically significant slowdown (>5% at p=0.05).
- Noise floor: record machine load and CPU governor state when seeding baselines.