{
  "slug": "value-log",
  "term": "Value log",
  "aliases": [
    "vLog"
  ],
  "definition": "A value log is an append-oriented record store whose values are located through a separate index.",
  "note": "WiscKey includes keys and length fields in its log records; moving live records also changes their index references. A value log is not automatically a write-ahead log. [wisckey]",
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "related": [
    "key-value-separation",
    "lsm-tree",
    "database-write-amplification"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "citations": [
    {
      "id": "wisckey",
      "title": "Lanyue Lu, Thanumalayan Sankaranarayana Pillai, Andrea C. Arpaci-Dusseau and Remzi H. Arpaci-Dusseau. WiscKey: Separating Keys from Values in SSD-conscious Storage. USENIX FAST 2016, pp. 133-148, sections 3.2-3.3 and 4.",
      "url": "https://www.usenix.org/system/files/conference/fast16/fast16-papers-lu.pdf",
      "accessed": "2026-10-12"
    },
    {
      "id": "hesela-kv",
      "title": "Key-value separation: the cleaning bill moves elsewhere",
      "url": "https://hesela.com/analyses/key-value-separation-cleaning-cost/",
      "accessed": "2026-10-12"
    }
  ],
  "updated": "2026-10-12"
}