Phase 1.6 (CLI flags + dev_features/holdout_features stash) and Phase
1.7 (set_test_data_from_slices observer + test_features stash) landed
the data-flow scaffolding; both deferred the actual eval consumer.
This task wires both atomically as parallel evaluator instances:
- dev_evaluator: Option<GpuBacktestEvaluator> -- lazy-init after final
fold, fires once against Q8 dev_features (when dev_quarters > 0)
- test_evaluator: Option<GpuBacktestEvaluator> -- lazy-init per fold,
fires inside the fold loop against the WF test slice (when
fold.test_end > fold.test_start)
Architectural choice: parallel evaluator instances (NOT window-swap on
val_evaluator). Window-swap would require invalidating the CUDA graph
between val and dev/test runs -- fragile, and a direct violation of
pearl_no_host_branches_in_captured_graph. Parallel instances mirror
val_evaluator's lazy-init pattern (TLOB sync, ISV signal pointer,
training_mode = false toggle). Implementation lives behind a single
shared helper `launch_extra_eval` keyed on an `ExtraEvalKind` enum so
Dev / Test share TLOB / ISV / config setup verbatim.
HEALTH_DIAG additions:
HEALTH_DIAG[N]: dev_eval dev_sharpe_net=... dev_calmar=... dev_max_dd=... dev_trades=...
HEALTH_DIAG[N]: test_slice fold=K test_sharpe_net=... test_calmar=... test_max_dd=... test_trades=...
The *_sharpe_net key uses the fused-metrics-kernel cost-aware Sharpe
(post-Phase-1.1.b split -- already includes tx_cost_bps + spread_cost
via the env-step PnL feed); when Phase 1.2.b cost-net sharpe lands, the
key name is preserved so the aggregator-script contract holds.
Atomic per feedback_no_partial_refactor: both eval calls + both
evaluator fields + both HEALTH_DIAG lines + audit doc all in this
commit. No parallel paths, no feature flags. Dev_eval runs synchronously
via evaluate_dqn_graphed (one-shot, no async pipelining benefit since
it doesn't fire per-epoch); val path stays async.
Sealed Q9 holdout remains untouched -- Phase 4.3 will load Q9 via a
separate eval-only entry point (NOT train_walk_forward). The Phase 1.6
debug_assert sealed-slice guard catches accidental future refactors.
Verified: cargo check -p ml --features cuda clean; ml lib suite holds
946 pass / 13 fail baseline; the existing Phase 1.7 oracle test
set_test_data_from_slices_fires_observer_and_stashes still passes.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
d7f60d4dd7