{
  "slug": "nvme-multipath-io-policy",
  "term": "NVMe multipath I/O policy",
  "aliases": [
    "NVMe iopolicy"
  ],
  "definition": "An NVMe multipath I/O policy is a host-side rule for choosing among eligible routes to one namespace.",
  "note": "Linux v6.12 provides numa, round-robin and queue-depth policies. ANA preference takes precedence over load distribution. The queue-depth implementation compares controller-level active-request counters, not just a namespace's outstanding I/O. The module parameter supplies a default; inspect the existing subsystem's iopolicy separately. [linux-code]",
  "related": [
    "multipath-nvme",
    "asymmetric-namespace-access"
  ],
  "citations": [
    {
      "id": "linux-code",
      "title": "Linux v6.12, drivers/nvme/host/multipath.c: ANA selection, controller nr_active accounting and subsystem iopolicy.",
      "url": "https://github.com/torvalds/linux/blob/v6.12/drivers/nvme/host/multipath.c",
      "accessed": "2026-10-15"
    },
    {
      "id": "linux-ana",
      "title": "Linux kernel documentation: native NVMe multipath policies.",
      "url": "https://docs.kernel.org/admin-guide/nvme-multipath.html",
      "accessed": "2026-10-15"
    },
    {
      "id": "hesela-paths",
      "title": "Hesela: NVMe multipath: ANA access states and Linux path policies",
      "url": "https://hesela.com/analyses/nvme-multipath-ana-path-selection/",
      "accessed": "2026-10-15"
    }
  ],
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-15"
}