{
  "slug": "tmpfs",
  "term": "tmpfs",
  "aliases": [
    "Temporary filesystem (Linux)",
    "Linux tmpfs"
  ],
  "definition": "tmpfs is a Linux filesystem whose contents reside in virtual memory and may use swap unless swapping is disabled for that mount.",
  "note": "The filesystem grows with its contents; size is an allocation ceiling, not reserved RAM. The separate nr_inodes limit can be exhausted even when byte capacity remains. Unmounting discards the files. [tmpfs-man] [tmpfs-v612]\n\nThe noswap mount option, available since Linux 6.4, disables swapping for that instance. It does not change every internal shared-memory object or other tmpfs mount. Swap use does not turn a temporary filesystem into persistent file storage. [tmpfs-man] [tmpfs-v612]",
  "related": [
    "memfd-create",
    "memory-mapped-file",
    "page-cache",
    "zram",
    "zswap"
  ],
  "citations": [
    {
      "id": "tmpfs-v612",
      "title": "Linux 6.12: tmpfs, swap and per-mount limits",
      "url": "https://docs.kernel.org/6.12/filesystems/tmpfs.html",
      "accessed": "2026-11-14"
    },
    {
      "id": "tmpfs-man",
      "title": "Linux man-pages: tmpfs(5), dynamic allocation and noswap",
      "url": "https://man7.org/linux/man-pages/man5/tmpfs.5.html",
      "accessed": "2026-11-14"
    }
  ],
  "advantages": [],
  "limitations": [],
  "provenance": [
    "Source synthesis checked against Linux 6.12 documentation; noswap introduction checked in tmpfs(5).",
    "No swapping, memory-pressure benchmark or reboot experiment was performed for this definition."
  ],
  "status": "shipping",
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-11-14"
}