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Mojo struct
DistributedAllReduceSum
struct DistributedAllReduceSum
Registers the mo.distributed.allreduce.sum graph op with the graph compiler.
Implemented traits
Methods
execute
static def execute[dtype: DType, rank: Int, target: StringSpan[ImmStaticOrigin], _trace_name: StringSpan[ImmStaticOrigin], group_size: Int = Int(0)](outputs: _FusedOutputVariadicTensors[static_specs=outputs.static_specs], inputs: VariadicTensors[IOSpec[_, _].Input, static_specs=inputs.static_specs], signal_buffers: VariadicTensors[IOSpec[_, _].MutableInput, static_specs=signal_buffers.static_specs], dev_ctxs_input: DeviceContextArray)
Distributed allreduce operation implementation for sum reduction.
Limitations: - Maximum of 8 GPUs supported (matches MAX_GPUS in comm/sync.mojo) - Tensor element count must be multiple of SIMD width (per allreduce.mojo) - Requires identical tensor shapes within each allreduce group
Parameters:
- dtype (
DType): Element type of the input and output tensors. - rank (
Int): Tensor rank (number of dimensions) of the inputs and outputs. - target (
StringSpan[ImmStaticOrigin]): Target device string for tracing. - _trace_name (
StringSpan[ImmStaticOrigin]): Trace name for profiling. - group_size (
Int): Number of devices per independent allreduce group; must evenly divide the total number of devices. Zero (the attribute default) means all devices form one group.
Args:
- outputs (
_FusedOutputVariadicTensors[static_specs=outputs.static_specs]): Output tensors (one per GPU) to store reduced results. - inputs (
VariadicTensors[IOSpec[_, _].Input, static_specs=inputs.static_specs]): Input tensors (one per GPU) containing values to reduce. - signal_buffers (
VariadicTensors[IOSpec[_, _].MutableInput, static_specs=signal_buffers.static_specs]): Preallocated synchronization buffers for cross-GPU coordination. - dev_ctxs_input (
DeviceContextArray): Device contexts for participating GPUs.