{
  "slug": "staggered-reconstruction",
  "term": "Staggered reconstruction",
  "aliases": [
    "staggered rebuild"
  ],
  "definition": "Staggered reconstruction rebuilds missing data in successive source-disk groups, limiting simultaneous disk activity.",
  "note": "Pergamum folds each source region into a disk-resident partial result. With m sources processed individually, each target location is written m times and reread m - 1 times. This is a reconstruction schedule, not a change to the erasure code. [pergamum08]",
  "status": "research",
  "advantages": [],
  "limitations": [
    {
      "text": "Limiting simultaneously active disks does not by itself establish lower total energy or faster recovery.",
      "citationIds": [
        "pergamum08"
      ]
    }
  ],
  "related": [
    "maid",
    "power-aware-coding"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-11-09",
  "citations": [
    {
      "id": "pergamum08",
      "title": "Storer, Greenan, Miller and Voruganti. Pergamum. FAST 2008, section 4.3.2.",
      "url": "https://www.usenix.org/legacy/event/fast08/tech/full_papers/storer/storer.pdf",
      "accessed": "2026-11-09"
    },
    {
      "id": "hesela-example",
      "title": "Hesela: explicit batched-XOR accounting, assumptions and executable tests",
      "url": "https://hesela.com/analyses/sleeping-disks-partial-reconstruction/#staggered-reconstruction",
      "accessed": "2026-11-09"
    }
  ]
}