{"record":{"id":"43d47f138470ae06","repo":"rohitg00/ai-engineering-from-scratch","slug":"unknown-op-op-43d47f","errorCode":null,"errorMessage":"unknown op {op}","messagePattern":"unknown op (.+?)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"phases/19-capstone-projects/76-collective-ops-from-scratch/code/main.py","lineNumber":229,"sourceCode":"    dtype = getattr(torch, dtype_str)\n    tensor = torch.frombuffer(bytearray(tensor_bytes), dtype=dtype).reshape(shape).clone()\n    if op == \"allreduce\":\n        dist.all_reduce(tensor, op=dist.ReduceOp.SUM)\n        out = tensor\n    elif op == \"broadcast\":\n        dist.broadcast(tensor, src=0)\n        out = tensor\n    elif op == \"allgather\":\n        gathered = [torch.zeros_like(tensor) for _ in range(world_size)]\n        dist.all_gather(gathered, tensor)\n        out = torch.cat(gathered)\n    elif op == \"reduce_scatter\":\n        chunks = [c.contiguous() for c in tensor.chunk(world_size)]\n        recv = torch.zeros_like(chunks[0])\n        dist.reduce_scatter(recv, chunks, op=dist.ReduceOp.SUM)\n        out = recv\n    else:\n        raise ValueError(f\"unknown op {op}\")\n    out_queue.put((rank, out.clone()))\n    out_queue.close()\n    out_queue.join_thread()\n    os._exit(0)\n\n\ndef gloo_reference(op: str, world_size: int,\n                   per_rank_tensors: list) -> list:\n    \"\"\"Run the same operation through torch.distributed gloo for verification.\n\n    Uses file-based init (file:// URI) because TCP init through libuv has\n    known issues on macOS with concurrent process group creation.\n    \"\"\"\n    ctx = mp.get_context(\"spawn\")\n    out_queue = ctx.Queue()\n    init_dir = tempfile.mkdtemp(prefix=\"aie_gloo_\")\n    init_file = os.path.join(init_dir, \"rendezvous\")\n    iface = _loopback_iface()","sourceCodeStart":211,"sourceCodeEnd":247,"githubUrl":"https://github.com/rohitg00/ai-engineering-from-scratch/blob/39ea8a1c6d0b61f071226eff7ede4d4105fed820/phases/19-capstone-projects/76-collective-ops-from-scratch/code/main.py#L211-L247","documentation":"Error \"unknown op {op}\" thrown in rohitg00/ai-engineering-from-scratch.","triggerScenarios":"Thrown at phases/19-capstone-projects/76-collective-ops-from-scratch/code/main.py:229 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"39ea8a1c6d0b61f071226eff7ede4d4105fed820","analyzedAt":"2026-08-26T03:13:46.626Z","schemaVersion":2},"datasetVersion":"2026-08-26T07:17:17.940Z"}