{
  "provenance": "Measurements from our standalone storage harnesses on 25 October 2026. Local filesystem paths omitted; recorded numeric results preserved.",
  "scope": "Standalone macOS random-read and split-disk harnesses, not end-to-end DwarfStar inference. No network measurements are included in this dataset.",
  "randomRead": [
    {
      "label": "internal",
      "size_bytes": 2147483648,
      "read_size": 264,
      "single_264": {
        "count": 65120,
        "mean_us": 60.988248955773955,
        "p50_us": 64.25,
        "p90_us": 81.542,
        "p99_us": 90.458,
        "p999_us": 122.416,
        "max_us": 1096.541,
        "elapsed_s": 4.000048957997933,
        "iops": 16279.800743387214,
        "mb_s": 4.297867396254225
      },
      "parallel4_264": {
        "count": 247648,
        "mean_us": 64.09325665056855,
        "p50_us": 68.083,
        "p90_us": 84.417,
        "p99_us": 108.958,
        "p999_us": 157.458,
        "max_us": 1199.125,
        "threads": 4,
        "elapsed_s": 4.004094292002264,
        "total_reads": 247648,
        "iops": 61848.69334736934,
        "mb_s": 16.328055043705508
      },
      "single_4096": {
        "count": 30870,
        "mean_us": 64.3914156138646,
        "p50_us": 68.375,
        "p90_us": 83.208,
        "p99_us": 98.083,
        "p999_us": 129.5,
        "max_us": 180.417,
        "elapsed_s": 2.000031624978874,
        "iops": 15434.755938084767,
        "mb_s": 63.22076032239521
      }
    },
    {
      "label": "samsung4tb",
      "size_bytes": 101377628352,
      "read_size": 264,
      "single_264": {
        "count": 39532,
        "mean_us": 100.6254235050086,
        "p50_us": 98.167,
        "p90_us": 112.292,
        "p99_us": 217.417,
        "p999_us": 294.333,
        "max_us": 4733.875,
        "elapsed_s": 4.000012125005014,
        "iops": 9882.97004223467,
        "mb_s": 2.6091040911499532
      },
      "parallel4_264": {
        "count": 131277,
        "mean_us": 121.44305141037654,
        "p50_us": 98.625,
        "p90_us": 114.25,
        "p99_us": 170.917,
        "p999_us": 2048.083,
        "max_us": 36790.459,
        "threads": 4,
        "elapsed_s": 4.0136189999757335,
        "total_reads": 131277,
        "iops": 32707.887819146188,
        "mb_s": 8.634882384254594
      },
      "single_4096": {
        "count": 19916,
        "mean_us": 99.92837366941153,
        "p50_us": 99.792,
        "p90_us": 115.375,
        "p99_us": 128.625,
        "p999_us": 153.834,
        "max_us": 218,
        "elapsed_s": 2.0000117080053315,
        "iops": 9957.941706182706,
        "mb_s": 40.78772922852436
      }
    }
  ],
  "splitDisk": {
    "note": "Quick concurrent 264-byte random-read benchmark (Apple M5 Ultra, 2026-10-25). Several runs; per-read values are raw pread times, batch times include Python harness sync overhead. Run-to-run spread is large (p99 varies up to ~50%).",
    "runs": [
      {
        "label": "8 readers, internal only",
        "readers": 8,
        "read_p50_us": 86.125,
        "read_p99_us": 264.75,
        "read_max_us": 928.834,
        "batch_p50_us": 194.75,
        "batch_p99_us": 400.917
      },
      {
        "label": "8 readers, split 4+4",
        "readers": 8,
        "read_p50_us": 93.375,
        "read_p99_us": 149.625,
        "read_max_us": 1007.125,
        "batch_p50_us": 203.625,
        "batch_p99_us": 312.292
      },
      {
        "label": "8 readers, Samsung only",
        "readers": 8,
        "read_p50_us": 103.458,
        "read_p99_us": 171,
        "read_max_us": 670.916,
        "batch_p50_us": 226.667,
        "batch_p99_us": 346.791
      },
      {
        "label": "12 readers, internal only",
        "readers": 12,
        "read_p50_us": 88.584,
        "read_p99_us": 185.625,
        "read_max_us": 2564.5,
        "batch_p50_us": 247.584,
        "batch_p99_us": 504.417
      },
      {
        "label": "12 readers, Samsung only",
        "readers": 12,
        "read_p50_us": 106.833,
        "read_p99_us": 200.75,
        "read_max_us": 626.041,
        "batch_p50_us": 288.417,
        "batch_p99_us": 506.25
      },
      {
        "label": "12 readers, split 6+6",
        "readers": 12,
        "read_p50_us": 97.709,
        "read_p99_us": 189.792,
        "read_max_us": 2529.042,
        "batch_p50_us": 262.459,
        "batch_p99_us": 508.75
      },
      {
        "label": "24 readers, internal only",
        "readers": 24,
        "read_p50_us": 140.625,
        "read_p99_us": 328.167,
        "read_max_us": 1166.583,
        "batch_p50_us": 483.167,
        "batch_p99_us": 892.584
      },
      {
        "label": "24 readers, Samsung only",
        "readers": 24,
        "read_p50_us": 119.417,
        "read_p99_us": 314.333,
        "read_max_us": 898.542,
        "batch_p50_us": 464.333,
        "batch_p99_us": 936.458
      },
      {
        "label": "24 readers, split 12+12",
        "readers": 24,
        "read_p50_us": 145.709,
        "read_p99_us": 360.958,
        "read_max_us": 1189.5,
        "batch_p50_us": 487.292,
        "batch_p99_us": 1102.375
      },
      {
        "label": "48 readers, split 24+24",
        "readers": 48,
        "read_p50_us": 235.292,
        "read_p99_us": 594.959,
        "read_max_us": 1947.083,
        "batch_p50_us": 974.416,
        "batch_p99_us": 1590.416
      },
      {
        "label": "24 readers, internal only (repeat)",
        "readers": 24,
        "round": 0,
        "read_p50_us": 144.084,
        "read_p99_us": 415.416,
        "read_max_us": null,
        "batch_p50_us": 486.5,
        "batch_p99_us": 918.292
      },
      {
        "label": "24 readers, split 12+12 (repeat)",
        "readers": 24,
        "round": 0,
        "read_p50_us": 145.625,
        "read_p99_us": 323.584,
        "read_max_us": null,
        "batch_p50_us": 482.875,
        "batch_p99_us": 840.541
      },
      {
        "label": "24 readers, Samsung only (repeat)",
        "readers": 24,
        "round": 0,
        "read_p50_us": 122.208,
        "read_p99_us": 377.5,
        "read_max_us": null,
        "batch_p50_us": 482.917,
        "batch_p99_us": 1162.958
      },
      {
        "label": "24 readers, internal only (repeat)",
        "readers": 24,
        "round": 1,
        "read_p50_us": 140.25,
        "read_p99_us": 331.792,
        "read_max_us": null,
        "batch_p50_us": 485.959,
        "batch_p99_us": 899.5
      },
      {
        "label": "24 readers, split 12+12 (repeat)",
        "readers": 24,
        "round": 1,
        "read_p50_us": 151.417,
        "read_p99_us": 477.208,
        "read_max_us": null,
        "batch_p50_us": 512.5,
        "batch_p99_us": 1431.75
      },
      {
        "label": "24 readers, Samsung only (repeat)",
        "readers": 24,
        "round": 1,
        "read_p50_us": 119.25,
        "read_p99_us": 329.375,
        "read_max_us": null,
        "batch_p50_us": 460.25,
        "batch_p99_us": 996.667
      }
    ]
  }
}