Phases 1 (controller) and 2 (sibling-table audit writes) landed in
prior commits. This commit adds the Phase 3 dry-run simulator
instead of the actual sleep-sweep scheduler, since Phase 3's value
is mostly in what we'd learn from running it — and the dry-run
captures those findings without committing to a scheduler design
prematurely.
bench/scripts/prometheus_sigma_sweep_dryrun.py — read-only
simulator that classifies §3 Target A (providence_cache) + Target B
(documents) sweep candidates, synthesizes ControllerBranches from
real shard data, runs the Phase 1 controller, reports decision
distribution + Phase-3-design findings. No LLM calls, no
mutations.
make prometheus-sweep-dryrun — produces a dated markdown report
at bench/results/prometheus-sigma-sweep-dryrun-YYYY-MM-DD.md.
Five findings surfaced by three dry-run iterations against the
live ~/.arborist/shards corpus (3.5M docs + 2839 providence_cache
rows) — captured in ticket §22:
1. chunk-size dominates Kelly threshold (must = Hermes
concurrency, not candidate pool)
2. flat capital_cost blocks every allocation (split kernel-cost
vs LLM-cost on the contract)
3. τ_qa=7d filters every CANONICAL_PROJECTION row (all 29 are
<7d old; need per-audit-mode τ)
4. Target B canonical-shape detection is the real headline
(~152K candidates extrapolated; controller correctly returns
MARGINAL on shape-match chunks)
5. quarantined rows correctly veto via cache_drift hard-veto
Mean per-branch controller latency in dry-run: 12.5 µs at
chunk_size=4. Phase 3's actual bottleneck is the witness fan-out
(Hermes calls), not the controller itself.
Ticket #000037 status flipped to in-progress with Phases 0+1+2
landed; Phase 3 scheduler remains future work but is informed by
the five findings.