[VSJoin-Exec] Experiment matrix and ablations for three mechanisms

[ZeroJustMe]

Goal

Build a reproducible experiment matrix to validate all three Chapter 3 ideas.

Experiment Plan

• Mechanism-I ablation:
  • rebuild period sweep
  • validity filter variants
  • staleness/latency trade-off
• Mechanism-II ablation:
  • route mode sweep (unicast/budgeted/broadcast)
  • fanout budget sweep
  • dedup overhead accounting
• Mechanism-III ablation:
  • rebalance period/threshold/cap sweep
  • skew intensity sweep
  • control-plane overhead and stability

Baselines (repo-implemented only)

• BruteForce
• IVF
• HNSW
• HDR-Tree
• LSH path
• ClusteredJoin
• S3J-style path

Reproducibility Package

• Config sets under config/
• Output conventions under test/result/...
• TSV/CSV summary templates
• One-command runbook for key figures

Mandatory Test Hook

• If Join/Join pipeline changed, run ./build/bin/test_join_datasource_modes and archive outputs.

Acceptance Criteria

• Each Ch5 proposition has matching runnable config and artifact path.