Research complete: both score-based and RRF merge fail 0.95 threshold.
Updated research doc with full RRF validation results and confidence intervals.
Added benchmark result reports and helper tests. Follow-up bead miroir-n6v
created for global-IDF preflight (dfs_query_then_fetch pattern).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Research doc updated with precise 95% CIs per query type. compare.py
now computes and reports confidence intervals. Kendall τ = 0.79
(95% CI [0.7873, 0.8006]) confirms raw score merging is not viable;
RRF already implemented in merger.rs as mitigation. Follow-up bead
created (miroir-zfo) for RRF quality validation.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Completed Plan §15 Open Problem #4 research on cross-shard score comparability.
## Key Finding
Average Kendall tau: 0.79 vs. 0.95 threshold — FAIL
Cross-shard score comparability is a significant issue:
- Common-term queries: τ = 0.15 (catastrophic)
- Local IDF statistics cause score inflation on small shards
- Documents from 10-doc shards outrank 93K-doc shard results
## Recommendation
Implement Reciprocal Rank Fusion (RRF) for result merging.
Follow-up bead: miroir-nsu
## Artifacts Added
- Benchmark infrastructure: tests/benches/score-comparability/
- Corpus generator with extreme shard skew (100× variance)
- Query generator (10K random queries across 5 types)
- BM25-based simulation with global vs local IDF
- Kendall tau comparison tool
- Full experimental results (τ = 0.79 ± 0.01, 95% CI)
- Research writeup: docs/research/score-normalization-at-scale.md
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Add rrqlite/openraft+SQLite reference project, correct raft-rs status
to maintenance mode, note openraft 0.10 edition 2024 requirement, and
add additional production users (Helyim, RobustMQ, rrqlite).
Decision unchanged: do not ship Raft in v0.x or v1.0, revisit before v2.0.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds 14 chaos tests validating zero-data-loss at the migration cutover
boundary under all AE/delta-pass configurations. Two new 3-node cluster
variants exercise multi-owner shard migration with cross-node drain
tracking.
Key results: 0/1M loss with AE+delta; 0/50K loss with delta alone;
~2% hypothetical loss with neither (hard-refused by policy). The
MigrationCoordinator blocks migration when both anti-entropy and delta
pass are disabled.
Also includes: anti-entropy cross-module validation gate, warning log
when AE disabled during migration, empirical results table in
docs/trade-offs.md, and plan §15 OP#1 status update to verified.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Full serde-derived struct tree covering every block in plan §4 (MiroirConfig,
NodeConfig, TaskStoreConfig, AdminConfig, HealthConfig, ScatterConfig,
RebalancerConfig, ServerConfig, ConnectionPoolConfig, TaskRegistryConfig) and
all 21 §13 advanced-capability sub-structs (ReshardingConfig through
SearchUiConfig with nested auth/rate-limit/CSP/analytics structs), plus §14
horizontal-scaling structs (PeerDiscoveryConfig, LeaderElectionConfig, HpaConfig).
Includes:
- Layered loading via config crate: built-in defaults → file → env overrides
- Config::validate() with 14 cross-field rules (HA requires redis, scoped_key
timing inversion, node group bounds, tenant affinity range checks, etc.)
- 10 unit tests: round-trip YAML, full plan example, minimal YAML defaults,
and validation rejection cases
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Survey openraft, raft-rs, and async-raft crates. Design a Raft-backed
TaskStore prototype using openraft with SQLite state machine. Analytical
benchmark against Redis across latency, throughput, memory, and ops
complexity. Decision: revisit before v2.0, do not ship in v0.x/v1.0 —
Raft fails the decision gate (worse on write latency and correctness
maturity despite removing the Redis dependency).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
- LICENSE: MIT (per plan §12)
- CHANGELOG.md: Keep a Changelog 1.1.0 skeleton with [Unreleased]
and [0.1.0] sections matching the awk extractor from plan §7
- .gitignore: Rust target/, editor junk; Cargo.lock kept in VCS
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
