torch.cuda.green_contexts.get_num_locality_domains

torch.cuda.green_contexts.get_num_locality_domains(device_id=None)

Return the device’s locality-domain count reported by CUDA.

Returns 1 when the required software is unavailable. With CUDA driver and bindings 13.4+, initializes the CUDA driver and queries the count. This query does not create a context when device_id is specified; invalid devices and failed driver queries raise an error. Initializing the driver can prevent CUDA use in subsequently forked children.

Parameters:

device_id (int, optional) – Device index. When None, uses the current PyTorch device, initializing PyTorch CUDA state if necessary.

Return type:

int