{
  "schemaVersion": 1,
  "kind": "bounded-native-api-observation",
  "generatedAt": "2026-11-05T23:49:34.574413+00:00",
  "repetitions": 5,
  "sourceSha256": {
    "probe.c": "8dbd0e2fe3859ba4b515c46f966af8be45101b8640e5607f40d0755dd091c283",
    "observe.py": "2c3883d381f60c31f465c3518c16397fc74430b53f59bc2640ace9fdc8d4e274"
  },
  "compiler": "cc (Ubuntu 13.3.0-6ubuntu2~24.04.1) 13.3.0",
  "compilerFlags": [
    "-std=c11",
    "-Wall",
    "-Wextra",
    "-Werror",
    "-O2"
  ],
  "python": "3.12.3",
  "method": "Fresh two-page self-owned file per trial, unlinked immediately, bytes checked and mapping mlocked; query after write, fsync, six range queries and two error controls.",
  "limits": "One host, locked tiny fixtures, no performance, eviction, permissions, race, power-loss or attack experiment. Dirty/writeback counts are observations, not required reproducibility invariants.",
  "observations": [
    {
      "kernel": "6.8.0-146-generic",
      "machine": "x86_64",
      "page_size": 4096,
      "filesystem_magic": "0xef53",
      "locked_pages": 2,
      "negative_controls": {
        "bad_fd_errno": 9,
        "bad_flags_errno": 22
      },
      "samples": [
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          "name": "after_write",
          "off": 0,
          "len": 8192,
          "nr_cache": 2,
          "nr_dirty": 2,
          "nr_writeback": 0,
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        },
        {
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        },
        {
          "name": "first_page",
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        },
        {
          "name": "last_byte_first_page",
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        },
        {
          "name": "cross_boundary",
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          "len": 2,
          "nr_cache": 2,
          "nr_dirty": 0,
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          "nr_evicted": 0,
          "nr_recently_evicted": 0
        },
        {
          "name": "second_page",
          "off": 4096,
          "len": 4096,
          "nr_cache": 1,
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        },
        {
          "name": "zero_length_to_end",
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        }
      ]
    },
    {
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      "filesystem_magic": "0xef53",
      "locked_pages": 2,
      "negative_controls": {
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        "bad_flags_errno": 22
      },
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          "name": "after_write",
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          "len": 8192,
          "nr_cache": 2,
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        {
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        },
        {
          "name": "last_byte_first_page",
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        },
        {
          "name": "cross_boundary",
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          "nr_cache": 2,
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          "nr_writeback": 0,
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        },
        {
          "name": "second_page",
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        },
        {
          "name": "zero_length_to_end",
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        }
      ]
    },
    {
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      "negative_controls": {
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        "bad_flags_errno": 22
      },
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        },
        {
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        },
        {
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        },
        {
          "name": "last_byte_first_page",
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        },
        {
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        },
        {
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        },
        {
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    },
    {
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      "filesystem_magic": "0xef53",
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      "negative_controls": {
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        "bad_flags_errno": 22
      },
      "samples": [
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        {
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        {
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        },
        {
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        {
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        }
      ]
    },
    {
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      "page_size": 4096,
      "filesystem_magic": "0xef53",
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      },
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        {
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        {
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  ]
}