{
  "slug": "mincore",
  "term": "mincore",
  "aliases": [
    "mincore(2)"
  ],
  "definition": "mincore is a system call that reports a page-residency vector for a mapped virtual-address range.",
  "note": "Only the low bit of each result byte is defined. The start address must be page-aligned; length rounds up to pages. Success returns zero, failure returns -1 with errno, and the snapshot may already be stale on return. [mincore-api]\n\nLinux v6.17 permits file-cache disclosure when the caller owns the inode, has the relevant capability, or passes the file write-permission check. Otherwise it returns all-one bytes for that mapping without measuring its residency. Opening a file read-only is not itself the deciding condition. [mincore-source]",
  "advantages": [],
  "limitations": [
    {
      "text": "Residency does not measure read latency, persistent storage or an application's cache-hit ratio.",
      "citationIds": [
        "hesela-probe"
      ]
    }
  ],
  "related": [
    "page-cache",
    "memory-mapped-file",
    "posix-fadv-dontneed",
    "rwf-nowait",
    "readahead"
  ],
  "citations": [
    {
      "id": "mincore-api",
      "label": "mincore(2)",
      "title": "Linux man-pages 6.19: mincore(2), residency snapshots and return values.",
      "url": "https://man7.org/linux/man-pages/man2/mincore.2.html",
      "accessed": "2026-10-17"
    },
    {
      "id": "mincore-source",
      "label": "Linux v6.17 mincore",
      "title": "Linux v6.17 mm/mincore.c: can_do_mincore, do_mincore and page-cache lookup.",
      "url": "https://raw.githubusercontent.com/torvalds/linux/v6.17/mm/mincore.c",
      "accessed": "2026-10-17"
    },
    {
      "id": "hesela-probe",
      "title": "Hesela. Five self-owned-file mincore observations, source and environment.",
      "url": "https://hesela.dev/research/cache-residency/result.json",
      "accessed": "2026-10-17"
    }
  ],
  "status": "shipping",
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-17"
}