ColossalAI/applications/ColossalMoE/colossal_moe/models/mixtral_layer.py

81 lines
3.0 KiB
Python

import torch
import torch.nn as nn
from transformers.models.mixtral.modeling_mixtral import MixtralDecoderLayer, MixtralSparseMoeBlock
from colossalai.lazy import LazyInitContext
from colossalai.moe import SparseMLP
class MixtralSparseMLP:
r"""
This is a wrapper around the apex fused layernorm implementation. It is meant to be used only with the from_native_module interface.
"""
def __init__(self) -> None:
raise NotImplementedError(
"FusedLayerNorm is not implemented as a physical class. "
"It is meant to be used only with the from_native_module interface convert a native pytorch layer norm module to FusedLayerNorm module provided by apex."
)
@staticmethod
def from_native_module(module: MixtralSparseMoeBlock, enable_kernel: bool) -> nn.Module:
r"""
Convert a native pytorch layer norm module to FusedLayerNorm module provided by apex,
and optionally marking parameters for gradient aggregation.
Args:
module (nn.LayerNorm): The native PyTorch LayerNorm module to be converted.
sp_partial_derived (bool): Whether this module's gradients are partially derived in sequence parallelism.
Returns:
nn.Module: Union[FastLayerNorm, FusedLayerNorm].
Raises:
AssertionError: If the provided module is not an instance of nn.LayerNorm.
"""
with torch.no_grad():
LazyInitContext.materialize(module)
# get the attributes of the module
moe_kwargs = dict(
num_experts=8,
hidden_size=module.hidden_dim,
intermediate_size=module.ffn_dim,
router_top_k=module.top_k,
router_norm=True,
router_loss=False,
# router_capacity_factor_train=
# router_capacity_factor_eval=
mlp_activation="silu",
mlp_gated=True,
# enable_load_balance=
# load_balance_tolerance=
# load_balance_beam_width=
# load_balance_group_swap_factor=
enable_kernel=enable_kernel,
# enable_comm_overlap=
# enable_hierarchical_comm=
return_gate_logits=True,
)
dtype = module.gate.weight.dtype
device = module.gate.weight.device
sparse_mlp = SparseMLP(**moe_kwargs).to(dtype).to(device)
return sparse_mlp
def replace_moe_layer(model: nn.Module, enable_kernel: bool = False) -> nn.Module:
"""
Reverse the replace layer operation
Args:
module (torch.nn.Module): The object of layer to shard
"""
if isinstance(model, MixtralDecoderLayer):
model.block_sparse_moe = MixtralSparseMLP.from_native_module(
model.block_sparse_moe, enable_kernel=enable_kernel
)
else:
for _, child in model.named_children():
replace_moe_layer(child, enable_kernel)