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Mojo function

task_id_for_device

def task_id_for_device(device_id: Int) -> Int

Maps a device ID to a preferred AsyncRT worker thread ID for CPU affinity.

Delegates to the shared C++ implementation in DeviceAffinity.cpp which handles explicit MODULAR_RUNTIME_DEVICE_TASK_CPU_IDS config, NUMA-inferred GPU-to-CPU core mapping, and round-robin fallback.

Intended for use by affinity-aware task launchers such as _create_task and _launch_device_collective. Pass -1 when no affinity hint is needed.

Args:

• ​device_id (Int): The integer device ID (e.g. the ordinal of a GPU device).

Returns:

Int: An AsyncRT worker thread index to use as desired_worker_id, or -1 if no affinity mapping is configured.