{
 "date": "2026-10-21",
 "decision": "invalid measurement",
 "change": "directed exit without the sender grid sync: each sending CTA flushes its TMA stores and releases its own arrival; receivers wait for round x sender CTAs; the last source CTA resets the slot counters (scratch build, selected per arm by PYTHONPATH)",
 "scope": "4 x H100, 2A2F, random, BF16, graphs, 24 SMs; three fresh-process repeats",
 "correctness": "BF16/FP8 small and large and the 3:1 and 1:3 small cases passed",
 "screens": [
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   "table": [
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   "table": [
    {
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    {
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    },
    {
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    },
    {
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    },
    {
     "tokens": 512,
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      "geomean_change_pct": 0.0,
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    },
    {
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     "head": {
      "median_us": 385.101,
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   ]
  }
 ],
 "conclusion": "Void: both arms recorded the same native digest (the screen's working directory shadowed PYTHONPATH), so the variant was not measured. Re-run with PYTHONSAFEPATH=1."
}