Single-thread cold-path-cadence kernel writes 8 per-expert utilization EMAs + 1 gate-entropy EMA into ISV slots [118..127), α=0.05. Same shape as h_s2_rms_ema_update / aux_heads_loss_ema_update. GPU-resident, CPU read-only per pearl_cold_path_no_exception_to_gpu_drives.md. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>