{
  "slug": "shingle-translation-layer",
  "term": "Shingle translation layer",
  "aliases": [
    "STL"
  ],
  "definition": "A shingle translation layer (STL) maps logical blocks to storage locations and manages writes around shingled magnetic recording constraints.",
  "note": "In drive-managed SMR, the translation layer runs in firmware and presents conventional rewritable logical blocks while hiding the internal band layout. [models]\n\nAn STL is not inherently drive firmware. Software emulators have implemented translation layers as Linux device-mapper targets. Static and dynamic mapping are different design choices, not synonyms for the term. [skylight]",
  "status": "shipping",
  "advantages": [],
  "limitations": [
    {
      "text": "A conventional interface does not by itself disclose the cleaning policy or guarantee a sustained-write rate.",
      "citationIds": [
        "models"
      ]
    }
  ],
  "related": [
    "device-managed-smr",
    "smr-persistent-cache",
    "garbage-collection-smr",
    "shingled-band",
    "ftl"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "citations": [
    {
      "id": "models",
      "title": "Zoned Storage: Shingled Magnetic Recording Hard Disks, interface implementations",
      "url": "https://zonedstorage.io/docs/introduction/smr",
      "accessed": "2026-10-19"
    },
    {
      "id": "skylight",
      "title": "Aghayev and Desnoyers. Skylight: a Window on Shingled Disk Operation. FAST 2015, sections 2, 3.1 and 4.5-4.7",
      "url": "https://www.usenix.org/system/files/conference/fast15/fast15-paper-aghayev.pdf",
      "accessed": "2026-10-19"
    }
  ],
  "updated": "2026-10-19",
  "provenance": [
    "Skylight section 3.1 describes research emulators; their behavior is not evidence that a particular commercial disk uses the same implementation."
  ]
}