ColossalAI/colossalai/auto_parallel/meta_profiler/meta_registry/embedding.py

53 lines
2.5 KiB
Python

from typing import List, Tuple
import torch
from colossalai._analyzer._subclasses.flop_tensor import flop_mapping
from colossalai._analyzer.fx.node_util import compute_size_in_bytes
from colossalai.auto_parallel.tensor_shard.sharding_strategy import MemoryCost, OperationDataType, TrainCycleItem
from ..registry import meta_register
__all__ = ["embedding_meta_info"]
@meta_register.register(torch.nn.Embedding)
def embedding_meta_info(*args, **kwargs) -> Tuple[TrainCycleItem, TrainCycleItem, List[torch.Tensor]]:
"""torch.nn.Embedding metainfo generator
Returns:
Tuple[TrainCycleItem, TrainCycleItem, List[torch.Tensor]]: compute cost, memory cost and forward inputs
"""
input_tensor = next(filter(lambda x: x.type == OperationDataType.ARG, args)).data
weight_tensor = next(filter(lambda x: x.type == OperationDataType.PARAM, args)).data
output_tensor = next(filter(lambda x: x.type == OperationDataType.OUTPUT, args)).data
# compute cost
fwd_compute_cost = flop_mapping[torch.ops.aten.embedding.default]([weight_tensor, input_tensor], [output_tensor])
bwd_compute_cost = flop_mapping[torch.ops.aten.embedding_dense_backward.default](
[output_tensor, weight_tensor], [weight_tensor]
)
compute_cost = TrainCycleItem(fwd=fwd_compute_cost, bwd=bwd_compute_cost, total=fwd_compute_cost + bwd_compute_cost)
# memory cost
# NOTE: currently in SPMD solver we always believe that there will be a new tensor created in forward
# NOTE: during the backward phase of torch.nn.Embedding, it seems when the input is large enough, it will
# have a temp memory which is kind of weird and we don't know the reason yet, so currently we just assume
# that there will be no temp memory, as the temp memory is significantly smaller than the gradient memory
fwd_memory_cost = MemoryCost(
activation=compute_size_in_bytes([input_tensor, output_tensor]), parameter=0, temp=0, buffer=0
)
bwd_memory_cost = MemoryCost(activation=compute_size_in_bytes([weight_tensor]), parameter=0, temp=0, buffer=0)
total_memory_cost = MemoryCost(activation=fwd_memory_cost.activation + bwd_memory_cost.activation)
memory_cost = TrainCycleItem(fwd=fwd_memory_cost, bwd=bwd_memory_cost, total=total_memory_cost)
# store fwd_in, fwd_buffer, fwd_out
fwd_in = [torch.zeros_like(input_tensor)]
fwd_buffer = []
fwd_out = [torch.zeros_like(output_tensor)]
return compute_cost, memory_cost, fwd_in, fwd_buffer, fwd_out