{
  "slug": "journal-guided-resynchronization",
  "term": "Journal-guided resynchronization",
  "aliases": [],
  "definition": "Journal-guided resynchronization uses filesystem recovery records to target RAID consistency checks after a crash.",
  "note": "Denehy and colleagues' FAST 2005 prototype combined ext3 declared mode with a verify-read request to software RAID. Declarations recorded data-write destinations before modification; verify-read checked a stripe and repaired inconsistent parity. Ordinary read-modify-write can retain a pre-existing parity error. [denehy]",
  "status": "research",
  "advantages": [
    "Reuses cross-layer information to narrow recovery work."
  ],
  "limitations": [
    "Historical prototype, not a current ext4 setting.",
    "Requires coordinated filesystem and RAID changes, not merely an existing journal."
  ],
  "related": [
    "write-intent-bitmap",
    "raid-write-hole",
    "partial-parity-log"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-25",
  "citations": [
    {
      "id": "denehy",
      "title": "Denehy, Arpaci-Dusseau and Arpaci-Dusseau. Journal-guided Resynchronization for Software RAID. FAST 2005, sections 4-5.",
      "url": "https://www.usenix.org/legacy/event/fast05/tech/full_papers/denehy/denehy_html/main.html",
      "accessed": "2026-10-25"
    },
    {
      "id": "hesela",
      "title": "Hesela: RAID write-hole recovery mechanisms",
      "url": "https://hesela.com/analyses/raid-write-hole-bitmap-ppl/#journal-guided",
      "accessed": "2026-10-25"
    }
  ]
}