{
  "status": "research",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-20",
  "slug": "effective-retention-time",
  "term": "Effective retention time",
  "aliases": [
    "temperature-equivalent retention time"
  ],
  "definition": "Effective retention time is the duration at a stated reference temperature that a specified model assigns the same retention effect as a given thermal exposure.",
  "note": "The reference temperature, activation energy, calibration range and measured endpoint belong with the value. HeatWatch separates this thermal clock from dwell history and uses temperature-history integration [heatwatch]. Equal arithmetic-mean temperatures need not give equal effective times. A time conversion does not by itself predict SSD shelf life or failure probability [hesela-method].",
  "related": [
    "data-retention",
    "nand-dwell-time",
    "nand-thermal-annealing",
    "cross-temperature-effect"
  ],
  "citations": [
    {
      "id": "heatwatch",
      "title": "Luo et al. HeatWatch. HPCA 2018, sections 4.2 and 5.2. DOI: 10.1109/HPCA.2018.00050.",
      "url": "https://www.cs.cmu.edu/~yixinluo/index_files/heatwatch_hpca18.pdf",
      "accessed": "2026-10-20"
    },
    {
      "id": "hesela-method",
      "title": "Hesela. Retention-clock worked calculations: inputs, method and limits.",
      "url": "https://hesela.dev/research/retention-clock/README.md",
      "accessed": "2026-10-20"
    },
    {
      "id": "hesela-analysis",
      "title": "Hesela. How many days does a hot half-hour represent?",
      "url": "https://hesela.com/analyses/3d-nand-retention-evidence/#retention-clock",
      "accessed": "2026-10-20"
    }
  ]
}