{
 "schema_version": "1.7.0",
 "id": "x_NXMC-2024-0058",
 "modified": "2026-10-19T02:33:38.839Z",
 "published": "2026-10-18T09:00:52.565Z",
 "summary": "phi-2: structural change at cb2f453 (2024-01-11)",
 "details": "phi-2: MLP width unset to 10240, KV heads unset to 32; derived parameters 1.61B to 2.78B (+1.17B, +2.34 GB of bf16 weights); rope_theta unset to 10000; every position embedding changes (2024-01-11).\n\nRepository: https://huggingface.co/microsoft/phi-2. Revisions from cb2f4533604d8b67de604e7df03bfe6f3ca22869 onward carry this change; a pin at d3186761bf5c4409f7679359284066c25ab668ee or earlier does not.\n\nChanged keys:\n- intermediate_size: unset -> 10240 (structural)\n- model_type: phi-msft -> phi (structural)\n- num_key_value_heads: unset -> 32 (structural)\n- rope_theta: unset -> 10000 (structural)\n\nThis record says what the change does mechanically. It is not a report that anything broke for anyone.",
 "affected": [
  {
   "ranges": [
    {
     "type": "GIT",
     "repo": "https://huggingface.co/microsoft/phi-2",
     "events": [
      {
       "introduced": "cb2f4533604d8b67de604e7df03bfe6f3ca22869"
      }
     ]
    }
   ],
   "database_specific": {
    "model": "microsoft/phi-2",
    "previous_revision": "d3186761bf5c4409f7679359284066c25ab668ee"
   }
  }
 ],
 "references": [
  {
   "type": "INTRODUCED",
   "url": "https://huggingface.co/microsoft/phi-2/commit/cb2f4533604d8b67de604e7df03bfe6f3ca22869"
  },
  {
   "type": "PACKAGE",
   "url": "https://huggingface.co/microsoft/phi-2"
  },
  {
   "type": "WEB",
   "url": "https://www.neurarch.com/changes-feeds/models/microsoft/phi-2.html"
  }
 ],
 "database_specific": {
  "source": "neurarch model change tracker",
  "model": "microsoft/phi-2",
  "kind": "structural",
  "classes": [
   "structural"
  ],
  "changed_keys": [
   {
    "file": "config",
    "key": "intermediate_size",
    "before": null,
    "after": 10240,
    "class": "structural"
   },
   {
    "file": "config",
    "key": "model_type",
    "before": "phi-msft",
    "after": "phi",
    "class": "structural"
   },
   {
    "file": "config",
    "key": "num_key_value_heads",
    "before": null,
    "after": 32,
    "class": "structural"
   },
   {
    "file": "config",
    "key": "rope_theta",
    "before": null,
    "after": 10000,
    "class": "structural"
   }
  ],
  "impact": {
   "memory": true,
   "serving": true,
   "tokenizer": false,
   "licence": null
  },
  "breaking": true,
  "breaking_rule": "https://www.neurarch.com/changes-feeds/advisories/index.json#breaking_rule",
  "consequence": {
   "params": {
    "before": 1610456064,
    "after": 2779520000
   },
   "weightsGbBf16": {
    "before": 3.221,
    "after": 5.559
   },
   "trainPeakGb": {
    "before": 66.018,
    "after": 274.321
   },
   "fingerprint": {
    "before": "d68ff415",
    "after": "7fefd770"
   },
   "context": null,
   "eos": null,
   "bos": null
  },
  "commit_date": "2024-01-11T17:03:31.000Z",
  "detected_at": "2026-10-18T09:00:52.565Z",
  "detected_by": "backfill",
  "days_since_first_commit": 28,
  "license": "CC-BY-4.0"
 }
}