{
  "campaign": "20261026-single-core-completion-supplement",
  "run_id": "20261026-single-core-completion-supplement-0008-a0",
  "original_run_id": "0008-a0",
  "spec": {
    "rows": 10000000,
    "job": "sort_string",
    "engine": "spark",
    "mode": "compute",
    "repeat": 0,
    "cores": 1,
    "heap": "96g",
    "memory": "128g",
    "kind": "single_core_supplement",
    "image_id": "sha256:215b09f971f3ac8d72022ea6e3157d80d88835ceb62899aecd829be0705e12b1"
  },
  "duration": 64.817740771,
  "window_monotonic": [
    1655725.430323528,
    1655790.248064299
  ],
  "window_utc": [
    1793026900.7738204,
    1793026965.591561
  ],
  "quality": {
    "sample_counts": {
      "cpu_cores": 12963,
      "memory_used_gib": 12964,
      "read_mib_s": 12963,
      "write_mib_s": 12963
    },
    "rate_span_fraction": 0.9998804188483257,
    "median_interval_seconds": 0.005000043543986976,
    "max_interval_seconds": 0.0071734103839844465,
    "collector_compute_one_core_fraction": 0.05362807997818385,
    "valid": true,
    "minimum_rate_samples": 4,
    "minimum_rate_span_fraction": 0.45,
    "duration_seconds": 64.817740771221,
    "cpu_resolution_note": "Sampling faster does not remove Linux CPU tick quantization; tiny-window peaks are not precise CPU demand."
  },
  "reference": {
    "spec": {
      "rows": 10000000,
      "job": "sort_string",
      "engine": "spark",
      "mode": "compute",
      "repeat": 0,
      "cores": 1,
      "heap": "96g",
      "memory": "128g",
      "kind": "single_core_supplement",
      "image_id": "sha256:215b09f971f3ac8d72022ea6e3157d80d88835ceb62899aecd829be0705e12b1"
    },
    "selected_repeat_ordinal": 2,
    "reference_campaign": "20261025T130534Z-full",
    "reference_run": "0283-a0",
    "reference_sha256": "e265ea28537fd4c4b6a5d5226de53d40026e9daf54186f823302db5670933470",
    "reference_purpose": "Output correctness only; reference uses 24 cores and is not a single-core timing observation."
  },
  "phases": [
    [
      0,
      64.817740771,
      "compute"
    ]
  ],
  "gap_policy": "Break on rejected snapshots/intervals and gaps over 20 ms; no interpolation or smoothing.",
  "collector_note": "Reuse the verified 5 ms collector and previous overhead gate; CPU 47 is physically separate from worker CPU 0. Gate was obtained on 24-core sum and is not a new single-core overhead estimate."
}
