From f9615439d5cad34d65aa5ae6208efd75afbf7dd6 Mon Sep 17 00:00:00 2001 From: ruvnet Date: Sun, 14 Jun 2026 06:45:56 +0000 Subject: [PATCH] deploy: f756a8af493a960a5217e39776685668bcdf19ad --- .../ADR-156-ruvector-fusion-beyond-sota.md | 4 +- .../adr/ADR-261-ruvector-graph-ann-index.md | 172 ++++++++++++++++++ 2 files changed, 174 insertions(+), 2 deletions(-) create mode 100644 api-docs/adr/ADR-261-ruvector-graph-ann-index.md diff --git a/api-docs/adr/ADR-156-ruvector-fusion-beyond-sota.md b/api-docs/adr/ADR-156-ruvector-fusion-beyond-sota.md index 4389fcd5..95493d30 100644 --- a/api-docs/adr/ADR-156-ruvector-fusion-beyond-sota.md +++ b/api-docs/adr/ADR-156-ruvector-fusion-beyond-sota.md @@ -102,7 +102,7 @@ The double-clone elimination is also correctness-neutral: all 100 `viewpoint`/`m | # | Candidate | What | Grade | Verdict | |---|-----------|------|-------|---------| -| **1** | **SymphonyQG** (SIGMOD 2025, public code) | Unified quantization + graph ANN; source reports **3.5–17× QPS over HNSW at equal recall**, pure-CPU / edge-portable. | **CLAIMED** (author-measured; **not reproduced on our hardware** — reproduction is future work) | **Lead beyond-SOTA candidate for the ruvector ANN path.** Propose as ACCEPTED-future; cite honestly as "claimed by source, reproduction pending." Best fit because the ruvector retrieval path (AETHER re-ID, sketch prefilter) is exactly an ANN problem and SymphonyQG is CPU/edge-portable like our deployment. | +| **1** | **SymphonyQG** (SIGMOD 2025, public code) | Unified quantization + graph ANN; source reports **3.5–17× QPS over HNSW at equal recall**, pure-CPU / edge-portable. | **MEASURED-direction-tested** (was CLAIMED) — **[ADR-261](ADR-261-ruvector-graph-ann-index.md)** built the missing HNSW baseline + a SymphonyQG-style 1-bit quantized-traversal variant and **measured** the ratio on our hardware. | **DONE — direction REFUTED at our scale (honest negative).** ADR-261 built the real HNSW baseline (**~25× QPS over linear scan at recall ≥0.99**, the substrate this row wanted) and a quantized variant. At N=10k the 1-bit Hamming traversal is **too coarse** — its best recall is 0.738, never reaching the ≥0.90 equal-recall point, so **no QPS win over float HNSW** (the SymphonyQG 3.5–17× is *not* reproduced by our 1-bit construction here). Caveat: **our HNSW + our 1-bit quant, not SymphonyQG's system**; expected crossover at large N + a multi-bit code. We did **not** tune to manufacture a speedup. | | **2** | **Multi-bit / Extended RaBitQ + unbiased estimator** | Extends our existing **1-bit** `sketch.rs` (ADR-084): Pass-2 rotation, multi-bit Pass-3, and the **real RaBitQ unbiased distance estimator** (Gao & Long SIGMOD 2024) reranking the candidate set from the 1-bit code + 8 B/vec side info (§11). | **MEASURED-on-our-hardware** (was CLAIMED) — rotation (§10), multi-bit (§10), and the estimator (§11) all implemented + benchmarked. Rotation lifts strict-K 36%→46%; multi-bit (≤4-bit) reaches 74% strict; **the estimator reaches 49.71% strict (cosine rerank), still short of 90%.** All clear 90% only with over-fetch (estimator improves the factor: 95% at candidate_k=24 vs sign 91.6%). | **DONE — RESOLVED-PARTIAL / NEGATIVE.** Rotation (§10) + estimator (§11) built and MEASURED. The honest negative (no strict-bar 90% from rotation, ≤4-bit, **or the unbiased estimator**) is recorded, not hidden. Over-fetch + Pass-2 is the path that meets the bar (ADR-084's "candidate set" pattern); the estimator lowers the over-fetch factor needed. | | **3** | **GraphPose-Fi-style learned antenna-attention + ChebGConv fusion head** | Would replace the current **untrained identity-projection + mean-pool** "attention" (the `CrossViewpointAttention` default is `ProjectionWeights::identity` — not a *learned* attention) with a learned graph fusion head. | **DATA-GATED** (per ADR-152 measurement (b): architecture is **NOT** the current bottleneck — **data is**) | **ACCEPTED-future, data-gated. Do NOT build now.** ADR-152's measured lesson was that swapping architecture without more/better paired data does not move PCK. Building a learned fusion head before the data exists would repeat the mistake ADR-155 §5 also flagged for GraphPose-Fi. | | — | **Cramér-Rao / sensor-placement** (`geometry.rs` CRB) | Investigated for a 2026 advance beating the textbook Fisher-information CRB already implemented. | **Investigated — NO ACTION** | **Cleared honestly.** No 2026 method beats the closed-form Fisher-information CRB for this 2-D bearing problem; our implementation is already correct SOTA. (Recording a negative result is a deliberate anti-slop signal.) The only CRB change this milestone is the §2.3 *GDOP* honesty fix, which is a labelling/quantity correction, not an algorithmic one. | @@ -138,7 +138,7 @@ The double-clone elimination is also correctness-neutral: all 100 `viewpoint`/`m The review surfaced more than this milestone scoped. Tracked here for a future ADR-156 milestone: -- **SymphonyQG reproduction** (§5 #1) — reproduce the 3.5–17× QPS-over-HNSW claim on our hardware before integrating into the ruvector ANN path. Currently CLAIMED-only. +- **SymphonyQG reproduction** (§5 #1) — **RESOLVED-DIRECTION-TESTED** (see [ADR-261](ADR-261-ruvector-graph-ann-index.md)). The missing HNSW baseline + a SymphonyQG-style 1-bit quantized-traversal variant were built and **MEASURED**: float HNSW is ~25× over linear scan at recall ≥0.99 (the baseline this gap needed), but our 1-bit quantized traversal is **too coarse to beat float HNSW at equal recall at N=10k** (best recall 0.738) — the 3.5–17× is **not reproduced** by our construction. Honest negative recorded; expected crossover is large N + a multi-bit traversal code. (Caveat: our HNSW + our 1-bit quant, not SymphonyQG's exact system.) - **Multi-bit / Extended RaBitQ** (§5 #2) — **RESOLVED-PARTIAL** (see §10). Pass-2 randomized rotation (FHT + seeded ±1 sign flips, `src/rotation.rs`) and a multi-bit Pass-3 experiment landed and were MEASURED against the ADR-084 ≥90% bar. **Honest result: rotation helps (+10pp at the strict bar) and Pass-2 reaches 90% with ~3× over-fetch, but NEITHER rotation nor multi-bit (up to 4-bit) clears the strict candidate_k==K 90% bar on the tested anisotropic distribution.** The original `1-bit sign quantization ships first; rotation/more-bits later if benchmark-measured top-K coverage drops below 90%` deferral is therefore retired: the rotation is built, the bar is characterised, and the residual gap is documented rather than deferred. - **Learned cross-viewpoint fusion head** (§5 #3, GraphPose-Fi-style) — **data-gated**: blocked on the paired multi-room data ADR-152 measurement (b) identified as the real bottleneck; do not build the architecture first. - **`CrossViewpointAttention` learned projections** — the default `ProjectionWeights::identity` + mean-pool is honest but unlearned; wiring real learned Q/K/V projections is part of the data-gated item above (no learned weights ⇒ the "attention" is currently a geometric-bias-weighted average, which the code/docs should keep stating plainly). diff --git a/api-docs/adr/ADR-261-ruvector-graph-ann-index.md b/api-docs/adr/ADR-261-ruvector-graph-ann-index.md new file mode 100644 index 00000000..acf76568 --- /dev/null +++ b/api-docs/adr/ADR-261-ruvector-graph-ann-index.md @@ -0,0 +1,172 @@ +# ADR-261: RuVector Graph-ANN Index — a real HNSW baseline + a SymphonyQG-style quantized variant, MEASURED + +| Field | Value | +|-------|-------| +| **Status** | Accepted | +| **Date** | 2026-06-14 | +| **Deciders** | ruv | +| **Codebase target** | `wifi-densepose-ruvector` — `hnsw.rs`, `hnsw_quantized.rs`, `ann_measure.rs`, `benches/ann_bench.rs`, docs | +| **Relates to** | ADR-084 (RaBitQ similarity sensor — 1-bit sketch), ADR-156 (RuVector beyond-SOTA sweep — §5 #1 SymphonyQG, §8/§10/§11 RaBitQ Pass-2/multi-bit/estimator), ADR-024 (AETHER re-ID), ADR-016/017 (RuVector integration) | +| **Scope** | Build the **missing HNSW graph-ANN baseline** in the ruvector retrieval path, build a **SymphonyQG-style quantized-traversal variant** on the same graph, and **MEASURE** the real recall/QPS ratio between them — closing the ADR-156 §5 #1 gap honestly. Resolves ADR-156 §8 backlog item **"SymphonyQG reproduction"** from **CLAIMED-only** to **MEASURED-direction-tested**. | + +--- + +## 0. PROOF discipline (this ADR's contract) + +This project has been publicly accused of "AI slop." This ADR answers with **evidence, not adjectives** — the same contract as ADR-154/156: + +- The HNSW index ships a **committed recall@10 correctness gate** (≥ 0.95 vs brute force on a planted-cluster fixture). Low recall means a graph bug; the gate is wired to fail in that case. It **did** fail first — and caught a real index-out-of-bounds bug in the insert path (§4) — which is exactly what a real gate is for. +- Every QPS/recall number below is **MEASURED** on this box with a committed, deterministic, `--no-default-features`-runnable measurement (`src/ann_measure.rs`, `ann_bench_report`) and a committed criterion bench (`benches/ann_bench.rs`). Both call **one** shared fixture/measurement module, so the bench and the report can never measure different graphs. +- The **headline result is an honest negative**: at our test scale the SymphonyQG-style quantized variant **does not beat float HNSW at equal recall** — the 1-bit Hamming traversal is too coarse to keep recall up. We report the real numbers, explain *why*, and state the expected large-N crossover. **We did not tune the quantized path to manufacture the 3.5–17× the source claims.** A measured negative + a scale caveat is a valid, publishable result. +- We are explicit that this is **OUR HNSW + OUR 1-bit quantization, not SymphonyQG's exact system**. It tests the **direction** of the claim on our hardware/data, not a 1:1 reproduction. + +Test machine: Windows 11, `cargo test --release`, `std::time::Instant` wall-clock. Numbers are warm medians on this box; the **ratio** is the claim, not the absolute QPS. + +Reproduce: +```bash +cd v2 && cargo test -p wifi-densepose-ruvector --no-default-features --release \ + ann_bench_report -- --nocapture +# Larger N: ANN_BENCH_N=50000 cargo test ... --release ann_bench_report -- --nocapture +cargo bench -p wifi-densepose-ruvector --bench ann_bench +``` + +--- + +## 1. Context + +The ruvector crate's retrieval path — AETHER re-ID hot-cache (ADR-024), the `sketch.rs` 1-bit prefilter (ADR-084), room fingerprinting — is, at its core, an **approximate nearest-neighbour (ANN)** problem: dense float embedding in, top-K similar ids out. But **the crate had no graph index**. Every `topk` was either a linear scan (`O(N·d)` per query) or a 1-bit Hamming prefilter over a linear scan. That is `O(N)` per query and does not scale. + +[ADR-156 §5 #1](ADR-156-ruvector-fusion-beyond-sota.md) graded **SymphonyQG** (SIGMOD 2025) the **lead beyond-SOTA ANN candidate**, citing the source's claim of **3.5–17× QPS over HNSW at equal recall**, but marked it **CLAIMED**: + +> *"author-measured; **not reproduced on our hardware** — reproduction is future work."* + +And ADR-156 §8 was blunt about *why* it could not be reproduced: **there was no HNSW baseline to compare against.** You cannot measure a ratio against a baseline that does not exist. This ADR builds that missing baseline, builds the quantized variant that tests the direction of the SymphonyQG bet, and measures the real ratio. + +--- + +## 2. Decision + +1. Add a correct, dependency-free **float HNSW** graph index (`hnsw.rs`): the real Malkov & Yashunin (TPAMI 2018) algorithm — multi-layer navigable small-world graph, `ef_construction` / `ef_search`, the Algorithm-4 neighbour-selection heuristic, seeded-deterministic level assignment, L2 + cosine. This is the **baseline** ADR-156 said was missing. +2. Add a **SymphonyQG-style quantized-traversal variant** (`hnsw_quantized.rs`): the *same* graph (same seed, same structure), but the beam search scores candidates with a **cheap 1-bit Hamming distance** over the RaBitQ Pass-2 rotated sign code (reusing `rotation.rs` + the sign-quantization of `sketch.rs`), then **exact-float reranks** the final candidate set. This is the SymphonyQG bet — cheaper per-node scoring, recovered by a final exact rerank. +3. **Measure** linear vs float-HNSW vs quantized-HNSW (recall@10, QPS, equal-recall ratios) on one deterministic planted-cluster fixture, and record the honest verdict against the SymphonyQG 3.5–17× claim. + +### Why 1-bit Hamming for the quantized traversal + +The crate already had the exact pieces SymphonyQG fuses: a deterministic orthogonal rotation (`rotation.rs`, RaBitQ Pass-2) and sign-quantization (`sketch.rs`). A 1-bit code compares by POPCNT Hamming — a few machine words, no per-dimension float work — so it is the cheapest possible traversal score and the most direct test of "can a quantized score keep the beam on the right path." The cost (measured below): the 1-bit code is a *coarse* angle proxy (ADR-156 §10 measured ~46% strict-K coverage for sign-only), and that coarseness is what limits recall here. + +--- + +## 3. Design + +### 3.1 `hnsw.rs` — float HNSW (the baseline) + +- **Graph.** `links[id][layer]` adjacency; layer 0 holds every node, higher layers exponentially sparser. `m_max` is `2·M` on layer 0, `M` above (the paper's asymmetric degree cap). +- **Insert.** Greedy-descend the upper layers to a good entry point, then for each layer from the node's level down to 0: `search_layer` for `ef_construction` candidates, `select_neighbours` (Algorithm 4 — keep a candidate only if it is closer to the new node than to any already-selected neighbour, giving diverse navigable edges), wire bidirectional edges, re-prune any neighbour that overflows `m_max`. The node is pushed into the arrays **before** wiring so every `links[*]` index is valid mid-insert (§4 — the bug the gate caught). +- **Search.** Greedy-descend layers `>0`, then best-first beam search of width `ef` on layer 0; return the closest `k`. Iterative (explicit heaps + visited set) — **no recursion**, bounded by the beam and the visited set. +- **Determinism.** Level assignment is the only randomness and is driven by a **seeded SplitMix64** (the exact pattern from `rotation.rs`) — never `Date::now`/OS RNG/unseeded `rand`. Same `(seed, params, insertion order)` ⇒ bit-identical graph and search (pinned by `hnsw_is_deterministic_for_seed`). +- **Robustness.** Empty index, `k==0`, `k>n`, single node, zero-dim, ragged query, `ef