{
 "date": "2026-10-21",
 "decision": "rejected",
 "change": "per-CTA counts: each source CTA adds its partial counts into FFN inboxes before its per-CTA arrival release; FFN ranks read them after every arrival (no SM0 grid-wide count reduction)",
 "motivation": "globaltimer trace at one token: source SM0 released its arrival 2.1-2.2 us after kernel start, other CTAs 0.45-0.51 us",
 "correctness": "BF16/FP8 small and large and the 3:1 and 1:3 small cases passed",
 "arms": {
  "afd": "per-CTA counts",
  "sm0_counts": "AFDEP_SM0_COUNTS=1 (shipped behavior)",
  "masked": "role_aware=False"
 },
 "screens": [
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    {
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     "sm0_counts": {
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     "masked": {
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    {
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   ]
  }
 ],
 "conclusion": "The SM0-count control was faster in every repeat at H2048 (-2.0% at one token, 20.65 vs 21.01 us) and in most H4096 cells: moving the prefix sums behind the arrival and completing remote count atomics before each release costs more than SM0's late release. Not shipped."
}