f2ggr confirmed K-loop wiring works mechanically but K=8 firing on
22 % of steps over-trained at b_size=1: KL excursions to 12.44
(vs prior 3.4e-4), policy overshoot, reward/trade -$0.585 → -$0.723.
Per `feedback_isv_for_adaptive_bounds` the K-loop config must live
in ISV, not as hardcoded values in the trainer. Two new slots:
RL_K_LOOP_DIVISOR_INDEX (450) — divides n_rollout_steps to get K
Default 2048 (matches ROLLOUT_BOOTSTRAP
so K=1 at controller bootstrap)
RL_K_LOOP_MAX_INDEX (451) — clamp ceiling on K
Default 4 (was hardcoded 8; halved
to prevent gradient overtraining)
K computation in step_with_lobsim now reads both from ISV:
K = clamp(isv[404] / isv[450], 1, isv[451])
Halves worst-case overtraining while preserving the controller
cascade activation (KL above noise floor, ε actively adapting,
ratio_clamp firing). Distribution shifts from K=8 @ 22% → K=4 @ 22%
(half the gradient updates in the high-noise case).
## Wiring
`rl_streaming_clamp_init.cu` extended to seed 5 ISV-resident design
constants (was 3): adv_var_clamp, td_kurt_clamp, adv_var_target,
k_loop_divisor, k_loop_max. Still one kernel call, no HtoD.
## Diag bake-in
JSONL `k_updates` field replaced with `k_loop` block:
k_loop.k_updates — actual K used this step
k_loop.divisor — current divisor (reads isv[450])
k_loop.max — current max (reads isv[451])
Post-hoc analysis can verify the K-computation by independently
recomputing K from isv[404] / k_loop.divisor.
## Slot allocation
RL_SLOTS_END: 450 → 452 (+2 new config slots).
## Test updates
G1 + G3 skip slots 450, 451 in sentinel-zero loop and assert seeded
values (2048.0 + 4.0) separately.
## Verified gates (local sm_86)
G1 isv_bootstrap ✅
G3 controllers ✅
G4 target_update ✅
integrated_smoke ✅
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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