fox 2026-05-21: (1) use REAL API token usage, not len//4; (2) the
substrate prefills a large retrieved CONTEXT as INPUT while solo feeds
~nothing, so per-completion-token over-charges the substrate — and per-
TOTAL-token UNDER-charges it (its mix is ~98% cheap prefill tokens).
Measured n=30 qwen-nothink/4090: substrate prefills ~6.6k input tok/query
(claim_lattice) vs solo ~52 — ~127x. Neither single per-token denominator
is honest; prefill (parallel, cheap/tok) and decode (autoregressive,
dear/tok) must be costed separately.
- OpenAICompatibleClient stashes data['usage'] as .last_usage (non-
invasive; return type unchanged).
- watt_bench captures real prompt_tokens + completion_tokens per call
(both arms), aggregates per cell, and energy_cogs reports gross +
marginal per BOTH 1k-total-tok and 1k-completion-tok plus the context
size. Prints the prompt/completion split.
- 12 tests incl. the prompt-context artifact (per-total cheap, per-
completion dear). Full suite 2540 passed.
The clean per-input-tok / per-output-tok split rides bench/watt_calibrate
(slope calibration; separate commit once validated live).
fox 2026-05-21: 'we dont touch card during retrieval'. Retrieval + verify
are CPU/SQLite on the orchestrator; the GPU is idle (at the shared, always-
on model-resident floor) during them. So the substrate does NOT 'hold the
card' through its wall-clock — the gross window integral over-counts by
charging that always-on floor for the seconds we spend retrieving (energy
that exists regardless of the query; the card serves other traffic then).
Correct attribution: the GPU cost of a query is its GENERATION energy only
(the marginal — burst above the serving floor). Relabel: marginal is the
headline GPU COGS; gross is demoted to a reference 'window total, not
query-attributable'. Print + energy_cogs docstring + stock-v1-config doc
updated. No math change (marginal was already right) — this corrects the
narration. Measured qwen-nothink/4090: substrate GPU COGS is LOW
(claim_lattice $0.21/M-tok, quote $0.83) — its real overhead is latency
(CPU retrieval), not GPU watts.
fox 2026-05-21: 'gen 200W' was a bug — joules/window blends the ~400W
generation bursts with the sub-100W gaps (retrieval/verify/network) into
a power state the card never sits at. A card occupies DISTINCT states
(idle / middle-idle = resident-between-requests / generation), differing
per card×model×server.
watt_probe.classify_power_bands(): largest-gap split of the window
samples into a low band (serving floor) and high band (generation draw)
+ duty cycle. Data-derived, never hardcoded — tested at two scales. The
worker emits the decomposition + raw samples; RemoteProbe/LocalProbe
expose band_stats() uniformly.
energy_cogs: marginal now taken against the measured SERVING FLOOR (the
standing cost of being ready), not deep idle; the blend is kept but
labelled window_mean_w. Reports idle/serving-floor/gen-draw/duty.
Cache-miss certainty (fox's question): the arborist arm runs
burn_existing=True (force-deletes any live providence row before
inference) and asserts cache_hits==0 with a loud warning + real_inference
flag — so we time real generation, never a SQLite lookup. Solo has no
cache path. 11 tests (energy math + band split). Validated live on the
isolated 4090: solo gen 308W/70%-duty vs substrate 396W/8.6%-duty —
substrate marginal/tok is LOWER, gross/tok higher (it holds the card
longer for retrieval).
fox 2026-05-21: compute cost-of-goods-sold by kWh vs tokens, with the
three power states (idle / warm-idle / generation) MEASURED per
card×model×server — never hardcoded (his 40/127/380 W were illustrative
of one 3090). The only operator input is --price-per-kwh (default 0.33
USD/kWh, a configurable site rate).
energy_cogs() (pure, unit-tested) decomposes measured generation energy
against the measured warm-idle baseline:
* gross — all measured joules over the window (all-in, includes the
warm-idle cost of keeping the model hot, amortized).
* marginal — joules ABOVE warm-idle: what one more request's burst
actually costs (clamped >=0).
kWh = J/3.6e6; $/1k-tok is the unit that compares to API pricing. Both
surface per cell + a COGS print line.
watt_bench's arborist arm now loads the frozen bench.stock_v1 policy
(--answer-mode, drift-guarded on non-reasoning) so cost is measured for
the SAME substrate the campaign grades. Cells record
window_start/end_unix so a post-hoc load_monitor queue-depth cross-ref
can flag organic-traffic contamination on the non-isolated single-slot
endpoints. 6 COGS tests; full suite 2534 passed.
Implements fox's 2026-05-20 architecture: don't ship shards to the
tight-on-disk GPU boxes; run the benchmark FROM the laptop (local
shards + retrieval + judge + workload loop, driving the worker's LLM
endpoint over the network) and have the worker boxes REPORT their own
power.
Adds a probe abstraction with two implementations behind one
start/stop/gpu_stats/cpu_stats interface:
- LocalProbe: wraps PowerSampler + CpuSampler (watt_bench runs ON the
GPU box — the original mode)
- RemoteProbe: orchestrates bench/watt_probe.py on a remote worker
over SSH (scp the stdlib probe once, launch --until-file detached,
touch the stop-file after the workload, fetch the JSON). The worker
needs no shards / arborist / venv.
--remote-gpu-host HOST selects RemoteProbe; --endpoint points at the
worker's endpoint. Idle baseline now records gpu_util_mean_pct and
flags ">5% ⇒ contaminated by live traffic" so the 3090-style
contamination (live hermes traffic polluting the baseline) is visible
in the output, not silent.
Verified end-to-end: laptop-driven n=2 solo qwen, power sampled on the
4090 over SSH — idle gpu 20.2W @ 0% util (clean) + cpu 86W; load
populated; report tagged mode=remote. The on-box LocalProbe path is
unchanged (omit --remote-gpu-host).
Report schema gains mode / remote_gpu_host / gpu_available /
cpu_energy_available. Per-cell records gpu+cpu+total joules/question.
Toward fox's next goal: score the full serving stack on quality AND
cost — {qwen, hermes} × {llama.cpp, vLLM} × {3090, 4090} × {solo,
arborist}, measuring CG% + GPU watts + CPU watts + joules/answer per
cell.
watt_bench.py — adds CpuSampler (Intel RAPL package energy via
/sys/class/powercap/intel-rapl:*/energy_uj). RAPL exposes a cumulative
microjoule counter, so energy-over-window is an end-minus-start diff
(handles wrap) — more accurate than integrating instantaneous power.
Sums multi-package. energy_uj is root-only by default (PLATYPUS /
CVE-2020-8694), so it degrades to available=False when locked;
--cpu-energy-cmd 'sudo cat {path}' supplies a privileged reader when a
sudo rule exists. Each cell now reports gpu/cpu/total joules-per-
question + gpu joules-per-token; the report records cpu_rapl_available.
Verified: graceful degradation when locked; RAPL diff math (1->4 MJ uJ
= 3.0 J, exact).
benchmark-matrix.md — expands the cost section to the full 16-cell
(model × engine × GPU × arm) design, the per-cell metric set (quality +
GPU + CPU energy), the serving-stack inventory from 2026-05-20 recon
(4090=qwen/llama.cpp, 3090=hermes/vLLM — each box has one engine + one
model today), and the buildout gap (vLLM+qwen, llama.cpp+hermes, cross-
GPU models). Notes idle-floor asymmetry (hermes/3090 ~127W vs
qwen/4090 ~20W) as a real optimizer input.
Harness is ready; the serving-config buildout + RAPL perm grant are the
remaining (ops, fox-directed) prerequisites to run the full matrix.
Two deliverables for the cost/energy axis of the constraint optimizer.
docs/benchmark-matrix.md — shareable spec of the control experiment:
the question, fixture (386 office-holder Qs with corpus-vintage gold),
the 3-model × 3-framing × 2-arm matrix (18 cells), the verdict
vocabulary + two reads (accuracy vs grounding-fidelity), the
deterministic code judge + its Opus calibration, the results-so-far
table, and the NEW cost dimension (tokens / latency / GPU watts /
joules-per-answer measured per GPU tier). Self-contained — readable
cold by David.
bench/watt_bench.py — GPU wattage harness. Samples nvidia-smi
power.draw on the inference GPU while driving a small representative
subset, reports mean/peak watts, trapezoid-integrated joules,
joules-per-question, and joules-per-token. Tags the GPU
(--gpu-label 3090|4090) so the optimizer can compare hardware tiers.
Idle-baseline sampling separates load draw from idle. Does NOT grade
(energy is independent of correctness); saves answers + per-question
timing to JSONL for a later quality-per-joule pass via
score_with_code_judge.
Designed to run ON the GPU box (the orchestrator has no GPU; the
3090/4090 live on the inference boxes). Degrades gracefully when
nvidia-smi is absent (energy fields null) so it is testable anywhere.
Verified: PowerSampler graceful degradation + trapezoid integration
(synthetic 100->200->200W over 2s = 350 J, exact).
The headline cost finding the optimizer must weight: qwen-think
reasoning = 1300-3300 tokens/answer vs qwen-nothink ~50-100 (20-50x),
for a workload where arborist+qwen-nothink already lands 82% CG. The
energy numbers will quantify whether reasoning's premium is ever
justified — grounding-fidelity per joule, not per answer.
