# Scoring Pipeline Latency Report

**Date:** 2026-03-27 12:46
**Corpus:** 47 docs, 401 chunks, 3.86 MB
**Config:** α=0.8, β=0.2, λ=0.05, over_fetch=50
**Runs:** 50 timed runs × 10 queries = 500 measurements
**top_k:** 10

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## Per-Stage Breakdown

| Stage | Median | P95 | P99 | Mean | % of Total |
|-------|--------|-----|-----|------|------------|
| Δt₁  sqlite-vec ANN | 0.499ms | 0.620ms | 1.191ms | 0.523ms | 71.4% |
| Δt₂  FTS5 keyword | 0.034ms | 0.047ms | 0.068ms | 0.035ms | 4.8% |
| Δt₃  RRF fusion | 0.044ms | 0.053ms | 0.064ms | 0.045ms | 6.4% |
| Δt₄  rerank_with_decay() | 0.077ms | 0.092ms | 0.124ms | 0.080ms | 11.0% |
| Δt₅  track_access() | 0.045ms | 0.068ms | 0.161ms | 0.053ms | 6.4% |
| Σ    Total with scoring | 0.699ms | 0.927ms | 1.480ms | 0.735ms | 100.0% |
| Σ-Δt₄-Δt₅  Without scoring | 0.577ms | 0.735ms | 1.266ms | 0.603ms | 82.5% |

**Scoring overhead (Δt₄+Δt₅)/Σ:** 17.42%
**Scoring absolute cost:** 0.122ms median

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## Interpretation

- **ANN lookup dominates** at 71% of total pipeline time (0.499ms)
- **rerank_with_decay()** costs 0.077ms — 11.0% of total
- **track_access()** costs 0.045ms — 6.4% of total
- **Combined scoring overhead: 17.42%** of end-to-end search time
- All stages remain **sub-millisecond** at P99