{
  "slug": "buffered-io",
  "term": "Buffered I/O",
  "aliases": [],
  "definition": "Buffered I/O is file access through an operating-system cache, allowing transfers between an application and storage to be decoupled.",
  "note": "For Linux iomap, buffered reads use page-cache folios and buffered writes dirty them for later writeback. This is distinct from a language runtime's stream buffer or an SSD's device cache. [iomap]",
  "advantages": [
    "Allows cache reuse and writeback rather than requiring every application transfer to reach storage immediately."
  ],
  "limitations": [
    "Successful buffer updates alone are not persistence evidence; mixing access paths can require coherence work."
  ],
  "related": [
    "page-cache",
    "direct-io",
    "write-back-cache",
    "fsync"
  ],
  "citations": [
    {
      "id": "iomap",
      "label": "Linux v6.17 iomap",
      "title": "Linux v6.17: iomap supported file operations, sections 2.2.1-2.2.3.",
      "url": "https://www.kernel.org/doc/html/v6.17/filesystems/iomap/operations.html",
      "accessed": "2026-10-14"
    }
  ],
  "status": "shipping",
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-14"
}