72 lines
4.1 KiB
Markdown
72 lines
4.1 KiB
Markdown
# Matched MRT DFG pilot preparation
|
||
|
||
Preparation only: this test-only extension reuses the existing runner and existing MRT
|
||
operator. GPU admission awaits reviewed MRT capability results; no pilot/full execution
|
||
is implied by CPU preflight. No production, historical SRT manifest, reference data,
|
||
periodic gate, geometry, initialization or observation algorithm is changed here.
|
||
|
||
## Selection and provenance
|
||
|
||
Use `--collision MRT` for **both** uniform D80 and refined root D40/fine D80. There are
|
||
no independently selectable collision models per case. Default remains SRT.
|
||
|
||
MRT verifies `data/refined_dfg/source_manifest_mrt.json`, pinned to reviewed numerical
|
||
source snapshot `3ea131e92c057843034f11a1c574301a2430dfce`, including the shared geometry,
|
||
pressure/cycle helpers and official reference. Test-only commits may change HEAD without
|
||
changing this numerical source pin. Plan, READY, case summaries and comparison separately
|
||
record `checkout_revision` and `checkout_dirty` using existing source-provenance helper;
|
||
the runner hash remains separate. Collision is recorded in every receipt, and full-mode
|
||
validation rejects missing or different collision labels in plan, either summary or either
|
||
READY receipt, in addition to existing source/runner/health/time checks.
|
||
|
||
The historical SRT manifest remains byte-for-byte unchanged. SRT on the MRT candidate
|
||
checkout deliberately fails that source pin; use a matching historical checkout via
|
||
`--source` for SRT. No fallback or automatic repinning is permitted. Historical SRT
|
||
failure/diagnostic evidence remains attached to its original source and runner hashes;
|
||
it cannot authorize an MRT full run. The existing failed-observation step-reporting
|
||
undercount is not changed in this narrowly scoped selection patch.
|
||
|
||
## Frozen physical comparison
|
||
|
||
All settings remain those documented in `refined_dfg.md`: U_lattice=.01, physical mean
|
||
U=1 m/s, D=.1 m, shear ν=.001 m²/s, fixed physical domain/body/wall planes, patch
|
||
(40,24,320,140), shifted FP32 double buffers, no LES/forcing/Jets, finest dx=.00125 m,
|
||
finest dt=.0000125 s, unchanged half-cell frame conversion and axis-specific phase.
|
||
Force interval accumulation, physical leaf mass, pressure interpolation, flux sampling,
|
||
safety thresholds, t*=5 pilot and t*=300 cap are unchanged. Existing accuracy/periodicity
|
||
criteria are imported unchanged. Both MRT cases are fresh runs; old MRT or SRT results
|
||
are not substituted as controls.
|
||
|
||
Both cases use the **existing MRT pressure-NEQ branch**: only unknown directions q2/6/8
|
||
are extrapolated. This differs from SRT's all-nine .5-damped branch; the retained
|
||
`srt_neq_damp=.5` configuration value is inactive under MRT. Backflow clamp remains off.
|
||
The outlet is still noncanonical relative to exact DFG do-nothing conditions.
|
||
|
||
The reused MRT operator keeps fixed kinetic rates `s_e=s_eps=s_q=1.2` on all levels;
|
||
only the shear rate follows existing per-level viscosity. Physical bulk relaxation
|
||
therefore differs between coarse and fine levels. Transfer operators and subcycling
|
||
are unchanged. This is the candidate's declared behavior, not a new fully mode-scaled
|
||
MRT transfer scheme. Do not tune rates, the patch or gates after seeing outcomes.
|
||
Capability smoke/parity gates do not establish DFG accuracy or speedup.
|
||
|
||
## CPU and admission commands
|
||
|
||
From this checkout:
|
||
|
||
```sh
|
||
python tests/unit/test_refined_dfg.py
|
||
python tests/validation/run_refined_dfg.py --collision MRT --mode plan --output /tmp/new-mrt-dfg-plan
|
||
```
|
||
|
||
After root verifies the candidate MRT root/parity/refinement capability results and admits
|
||
an idle device, the paired pilot may use the existing bounds and external watchdog:
|
||
|
||
```sh
|
||
CUDA_VISIBLE_DEVICES=<admitted-device> timeout --signal=TERM --kill-after=30s <hard-budget>s python tests/validation/run_refined_dfg.py --collision MRT --mode pilot --gpu-gates-approved --max-wall-seconds <soft-budget> --output <new-mrt-pilot-directory>
|
||
```
|
||
|
||
The flag is caller attestation, not evidence. An unhealthy first case prevents the second.
|
||
Existing strict pilot receipt validation and calibrated wall-time controls remain; full
|
||
mode is not being admitted as part of this preparation. Root must review both healthy
|
||
pilot outcomes and separately decide any full-run admission.
|