{"record":{"id":"19fd466946348373","repo":"rohitg00/ai-engineering-from-scratch","slug":"rank-cannot-recv-from-itself","errorCode":null,"errorMessage":"rank cannot recv from itself","messagePattern":"rank cannot recv from itself","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"phases/19-capstone-projects/76-collective-ops-from-scratch/code/main.py","lineNumber":65,"sourceCode":"    rank: int\n    world_size: int\n    out_queues: list\n    in_queues: list\n    byte_counter: object = None\n\n    def send(self, dst: int, tensor: torch.Tensor) -> None:\n        if dst == self.rank:\n            raise ValueError(\"rank cannot send to itself\")\n        payload = tensor.detach().clone().contiguous()\n        nbytes = payload.numel() * payload.element_size()\n        if self.byte_counter is not None:\n            with self.byte_counter.get_lock():\n                self.byte_counter.value += nbytes\n        self.out_queues[dst].put(payload)\n\n    def recv(self, src: int) -> torch.Tensor:\n        if src == self.rank:\n            raise ValueError(\"rank cannot recv from itself\")\n        return self.in_queues[src].get(timeout=RECV_TIMEOUT_S)\n\n\ndef build_queue_grid(ctx, world_size: int):\n    \"\"\"Allocate a (world_size, world_size) grid of queues using the given context.\"\"\"\n    grid = [[None] * world_size for _ in range(world_size)]\n    for src in range(world_size):\n        for dst in range(world_size):\n            if src != dst:\n                grid[src][dst] = ctx.Queue()\n    return grid\n\n\ndef mesh_from_grid(rank: int, world_size: int, grid, byte_counter) -> Mesh:\n    out_qs = [grid[rank][d] for d in range(world_size)]\n    in_qs = [grid[s][rank] for s in range(world_size)]\n    return Mesh(rank=rank, world_size=world_size,\n                out_queues=out_qs, in_queues=in_qs,","sourceCodeStart":47,"sourceCodeEnd":83,"githubUrl":"https://github.com/rohitg00/ai-engineering-from-scratch/blob/39ea8a1c6d0b61f071226eff7ede4d4105fed820/phases/19-capstone-projects/76-collective-ops-from-scratch/code/main.py#L47-L83","documentation":"Error \"rank cannot recv from itself\" thrown in rohitg00/ai-engineering-from-scratch.","triggerScenarios":"Thrown at phases/19-capstone-projects/76-collective-ops-from-scratch/code/main.py:65 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"}