{
  "slug": "read-disturb-recovery",
  "term": "Read Disturb Recovery (RDR)",
  "aliases": [
    "RDR",
    "read-disturb-oriented error recovery"
  ],
  "definition": "Read Disturb Recovery is a research technique that uses cell responses to additional disturbance to infer bit values before another ECC attempt.",
  "note": "Unlike reclaim, RDR targets already unreadable data rather than preventive relocation [cai-rdr]. Its probabilistic guesses can introduce errors. It is distinct from simply trying another sensing reference or issuing repeated host reads. The companion analysis explains why a lower aggregate error count is not a per-codeword recovery guarantee [hesela-rdr].",
  "status": "research",
  "advantages": [],
  "limitations": [
    {
      "text": "Planar MLC evidence does not establish effectiveness on arbitrary modern SSDs.",
      "citationIds": [
        "cai-rdr"
      ]
    }
  ],
  "related": [
    "read-disturb",
    "read-reclaim",
    "read-retry",
    "ldpc"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-20",
  "citations": [
    {
      "id": "cai-rdr",
      "title": "Cai et al. Read Disturb Errors in MLC NAND Flash Memory: Characterization, Mitigation, and Recovery. DSN 2015, sections 5.2-5.4. DOI: 10.1109/DSN.2015.49.",
      "url": "https://people.inf.ethz.ch/~omutlu/pub/flash-read-disturb-errors_dsn15.pdf",
      "accessed": "2026-10-20"
    },
    {
      "id": "hesela-rdr",
      "title": "Hesela: Read Disturb Recovery and codeword correction-radius counterexample",
      "url": "https://hesela.com/analyses/ssd-read-reclaim-hidden-writes/#read-disturb-recovery",
      "accessed": "2026-10-20"
    }
  ]
}