{
  "slug": "thin-pool",
  "term": "Thin pool",
  "aliases": [
    "LVM thin pool"
  ],
  "definition": "In Linux LVM, a shared allocation pool combining separate data and metadata logical volumes to back thin logical volumes and their snapshots.",
  "note": "Data% and Meta% measure different resources. Virtual volume sizes do not reserve pool capacity. The whenfull policy is independent of monitoring and automatic extension; growth requires free volume-group extents. [lvmthin] This term describes LVM/dm-thin, not every vendor's pool implementation.",
  "status": "shipping",
  "advantages": [],
  "limitations": [
    {
      "text": "Queuing writes while data space is exhausted does not prove successful completion.",
      "citationIds": [
        "dm-thin-source"
      ]
    }
  ],
  "related": [
    "thin-provisioning",
    "thin-pool-metadata",
    "lvm",
    "snapshot",
    "block-storage"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "citations": [
    {
      "id": "lvmthin",
      "title": "LVM2 lvmthin(7): pool components, usage counters and metadata repair",
      "url": "https://man7.org/linux/man-pages/man7/lvmthin.7.html",
      "accessed": "2026-10-17"
    },
    {
      "id": "dm-thin-source",
      "title": "Linux v6.12: dm-thin.c, pool modes, timeout, failed metadata operations and resize",
      "url": "https://github.com/torvalds/linux/blob/v6.12/drivers/md/dm-thin.c",
      "accessed": "2026-10-17"
    },
    {
      "id": "hesela-allocation",
      "title": "Hesela: Sparse files, preallocation and thin-pool capacity",
      "url": "https://hesela.com/analyses/sparse-files-preallocation-thin-capacity/",
      "accessed": "2026-10-17"
    }
  ],
  "updated": "2026-10-17"
}