René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Regression in Node.js 26.8.0: aligned Buffer pool breaks multi-byte typed-array views","articleBody":"### Version\n\n26.8.0, 26.8.1\n\n### Platform\n\n```text\nLinux, macOS, and Windows\n```\n\n### Subsystem\n\nBuffer\n\n### What steps will reproduce the bug?\n\n```\nconst buffer = Buffer.allocUnsafe(8);\n\nconsole.log({\n  node: process.version,\n  bufferLength: buffer.length,\n  backingLength: buffer.buffer.byteLength,\n  byteOffset: buffer.byteOffset,\n});\n\nnew Uint32Array(buffer.buffer, buffer.byteOffset); // throws RangeError\n```\n\n### How often does it reproduce? Is there a required condition?\n\nConsistently when:\n- \n- The Buffer is allocated from the default pool.\n- The typed-array element size does not divide the pool’s 65,599-byte backing allocation.\n- The typed-array constructor omits its explicit length.\n\nSmall files returned by readFileSync() meet these conditions.\n\n### What is the expected behavior? Why is that the expected behavior?\n\nCreating a typed-array view at the Buffer’s aligned byteOffset should not fail because of invisible padding after the Buffer view. This worked through Node.js 26.7.0.\n\n### What do you see instead?\n\n```\nRangeError: byte length of Uint32Array should be a multiple of 4\n```\n\nThe Buffer is eight bytes, but its pooled backing `ArrayBuffer` is 65,599 bytes.\n\n### Additional information\n\nThis appears related to [nodejs/node#65003](https://github.com/nodejs/node/pull/65003), which changed the pool to an aligned allocation of poolSize + alignment - 1 bytes.\n- This is a regression introduced in Node.js 26.8.0. The reproduction succeeds on 26.7.0 and consistently throws on 26.8.0 and 26.8.1.\n  - Node.js 26.7.0: backing length 65,536; succeeds\n  - Node.js 26.8.0+: backing length 65,599; throws\n- V8 is unchanged: 14.6.202.34-node.28\n- Supplying an explicit typed-array length works around the issue.\n- This surfaced in [rocksdb-js CI](https://github.com/HarperFast/rocksdb-js/actions/runs/33042839856/job/98464401877?pr=800).","author":{"url":"https://github.com/cb1kenobi","@type":"Person","name":"cb1kenobi"},"datePublished":"2026-08-27T19:30:02Z","url":"https://github.com/nodejs/node/issues/65601"}