{
  "slug": "rio-file-cache",
  "term": "Rio file cache",
  "aliases": [
    "RAM I/O file cache"
  ],
  "definition": "Rio is a research file cache designed to preserve in-memory file data across operating-system crashes using protection and warm-reboot recovery.",
  "note": "Its protected registry identifies buffers during recovery; metadata ordering still matters. The 1996 study excludes power outages from its experiments. [rio]\n\nHesela interpretation: classify evidence by failure type and recovery path before treating any cache as durable. This historical prototype is not a Linux configuration recommendation.\n\nVista is a separate transaction library layered on Rio; retaining file bytes alone does not group application updates into an atomic transaction. [vista]",
  "status": "research",
  "advantages": [],
  "limitations": [
    {
      "text": "No reproduction or modern-system performance claim is made here.",
      "citationIds": [
        "rio"
      ]
    }
  ],
  "related": [
    "write-back-cache",
    "write-through-cache",
    "crash-consistency",
    "power-loss-protection",
    "vista-recoverable-memory"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": {
    "date": "1996",
    "citationIds": [
      "rio"
    ]
  },
  "lastSeen": null,
  "citations": [
    {
      "id": "rio",
      "title": "Chen et al. The Rio File Cache: Surviving Operating System Crashes. ASPLOS VII (1996), sections 1-3, 5.",
      "url": "https://web.eecs.umich.edu/~pmchen/papers/chen96.pdf",
      "accessed": "2026-11-09"
    },
    {
      "id": "hesela",
      "title": "Hesela: Cache survival depends on the failure being tested.",
      "url": "https://hesela.com/analyses/raid-write-hole-bitmap-ppl/#rio-failure-scope",
      "accessed": "2026-11-09"
    },
    {
      "id": "vista",
      "title": "Lowell and Chen. Free Transactions with Rio Vista. SOSP 1997, section 4, PDF p. 4.",
      "url": "https://web.eecs.umich.edu/~pmchen/Rio/papers/lowell97.pdf",
      "accessed": "2026-11-09"
    }
  ],
  "updated": "2026-11-09",
  "provenance": [
    "Source review, not an independent fault-injection experiment."
  ]
}