{
  "slug": "lazyftl",
  "term": "LazyFTL",
  "aliases": [
    "Lazy flash translation layer"
  ],
  "definition": "LazyFTL is a research page-level flash translation layer that delays global mapping updates using separate update and cold-block areas.",
  "note": "LazyFTL separates a flash-resident global mapping table (GMT) from an SRAM update mapping table (UMT). The latter tracks pages in update and cold-block areas, including entries already propagated to GMT. [lazy2011]\n\nConversion batches mapping-page updates and reclassifies a block without copying its user pages; garbage collection still moves live pages and erases blocks. [lazy2011]\n\nRecovery must reconstruct volatile state. Section 6.4 outlines alternatives using NOR bookkeeping, mapping-area records or age-bounded block discovery; its repeated-conversion algorithm is not supplied. [lazy2011]",
  "status": "research",
  "advantages": [
    {
      "text": "Conversion can incorporate pending updates from other blocks when they share the mapping pages being rewritten.",
      "citationIds": [
        "lazy2011"
      ]
    }
  ],
  "limitations": [
    {
      "text": "Evaluation uses a trace-driven 1 GB SLC model with wear leveling omitted; it does not benchmark DFTL.",
      "citationIds": [
        "lazy2011"
      ]
    },
    {
      "text": "The recovery design is not evidence of power-cut validation on a shipping SSD.",
      "citationIds": [
        "lazy2011"
      ]
    }
  ],
  "related": [
    "ftl",
    "page-level-mapping",
    "mapping-cache",
    "translation-page",
    "garbage-collection"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-11-09",
  "citations": [
    {
      "id": "lazy2011",
      "title": "Ma, Feng and Li. LazyFTL: A Page-level Flash Translation Layer Optimized for NAND Flash Memory. SIGMOD 2011, sections 3.2, 4.1-4.2 and 6.1-6.4.",
      "url": "https://dbgroup.cs.tsinghua.edu.cn/ligl/papers/sigmod2011-lazyftl.pdf",
      "accessed": "2026-11-09"
    }
  ],
  "provenance": [
    "Historical source synthesis, not a reproduced implementation or measured device benchmark. Source locators and SHA-256 are retained in the research ledger."
  ]
}