Update the mixtral to use the better FusedMoE layer (#1081)

This commit is contained in:
Lianmin Zheng
2024-08-13 15:44:25 -07:00
committed by GitHub
parent 312e849255
commit ad3e4f1619
4 changed files with 57 additions and 258 deletions

View File

@@ -18,34 +18,25 @@ limitations under the License.
"""Inference-only Mixtral model."""
from typing import Iterable, Optional, Tuple
import numpy as np
import torch
import torch.nn.functional as F
from torch import nn
from transformers import MixtralConfig
from vllm import _custom_ops as ops
from vllm.config import CacheConfig
from vllm.distributed import (
get_tensor_model_parallel_rank,
get_tensor_model_parallel_world_size,
tensor_model_parallel_all_reduce,
)
from vllm.model_executor.layers.fused_moe import fused_moe
from vllm.distributed import get_tensor_model_parallel_world_size
from vllm.model_executor.layers.fused_moe import FusedMoE
from vllm.model_executor.layers.linear import (
QKVParallelLinear,
ReplicatedLinear,
RowParallelLinear,
)
from vllm.model_executor.layers.quantization.base_config import QuantizationConfig
from vllm.model_executor.layers.quantization.fp8 import Fp8Config
from vllm.model_executor.layers.rotary_embedding import get_rope
from vllm.model_executor.layers.vocab_parallel_embedding import (
DEFAULT_VOCAB_PADDING_SIZE,
ParallelLMHead,
VocabParallelEmbedding,
)
from vllm.model_executor.model_loader.weight_utils import default_weight_loader
from vllm.model_executor.utils import set_weight_attrs
from vllm.utils import print_warning_once
from sglang.srt.layers.layernorm import RMSNorm
from sglang.srt.layers.logits_processor import LogitsProcessor
@@ -69,216 +60,44 @@ class MixtralMoE(nn.Module):
hidden_size: int,
intermediate_size: int,
params_dtype: Optional[torch.dtype] = None,
tp_size: Optional[int] = None,
quant_config: Optional[QuantizationConfig] = None,
tp_size: Optional[int] = None,
prefix: str = "",
):
super().__init__()
self.tp_size = tp_size or get_tensor_model_parallel_world_size()
self.num_total_experts = num_experts
self.top_k = top_k
self.hidden_size = hidden_size
self.intermediate_size = intermediate_size // self.tp_size
self.quant_config = quant_config
# FIXME(pcmoritz): Make this more general to support different
# quantization schemes
self.use_fp8 = isinstance(quant_config, Fp8Config)
if params_dtype is None:
params_dtype = torch.get_default_dtype()
self.params_dtype = params_dtype
# Gate always runs at half / full precision for now.
self.gate = ReplicatedLinear(
self.hidden_size,
self.num_total_experts,
hidden_size,
num_experts,
bias=False,
params_dtype=self.params_dtype,
params_dtype=params_dtype,
quant_config=None,
prefix=f"{prefix}.gate",
)
if self.use_fp8 and self.quant_config.is_checkpoint_fp8_serialized:
params_dtype = torch.float8_e4m3fn
self.w13_weight = nn.Parameter(
torch.empty(
self.num_total_experts,
2 * self.intermediate_size,
self.hidden_size,
dtype=params_dtype,
)
self.experts = FusedMoE(
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
params_dtype=params_dtype,
reduce_results=True,
renormalize=True,
quant_config=quant_config,
tp_size=tp_size,
prefix=f"{prefix}.experts",
)
self.w2_weight = nn.Parameter(
torch.empty(
self.num_total_experts,
self.hidden_size,
self.intermediate_size,
dtype=params_dtype,
)
)
set_weight_attrs(
self.w13_weight,
{
"weight_loader": self.weight_loader,
},
)
set_weight_attrs(
self.w2_weight,
{
"weight_loader": self.weight_loader,
},
)
# Used for fp8.
self.w13_scale = None
self.w2_scale = None
self.a13_scale = None
self.a2_scale = None
if self.use_fp8:
# WEIGHT_SCALE (for fp8)
self.w13_scale = nn.Parameter(
torch.ones(self.num_total_experts, dtype=torch.float32),
requires_grad=False,
)
self.w2_scale = nn.Parameter(
torch.ones(self.num_total_experts, dtype=torch.float32),
requires_grad=False,
)
# If loading fp8 checkpoint, pass the weight loaders.
# If loading an fp16 checkpoint, do not (we will quantize in
# process_weights_after_loading()
if quant_config.is_checkpoint_fp8_serialized:
set_weight_attrs(
self.w13_scale,
{
"weight_loader": self.weight_loader,
},
)
set_weight_attrs(
self.w2_scale,
{
"weight_loader": self.weight_loader,
},
)
# ACT_SCALE (for fp8)
if quant_config.activation_scheme == "static":
if not quant_config.is_checkpoint_fp8_serialized:
raise ValueError(
"Found static activation scheme for checkpoint that "
"was not serialized fp8."
)
self.a13_scale = nn.Parameter(
torch.zeros(self.num_total_experts, dtype=torch.float32),
requires_grad=False,
)
self.a2_scale = nn.Parameter(
torch.zeros(self.num_total_experts, dtype=torch.float32),
requires_grad=False,
)
set_weight_attrs(
self.a13_scale,
{
"weight_loader": self.weight_loader,
},
)
set_weight_attrs(
self.a2_scale,
{
"weight_loader": self.weight_loader,
},
)
def weight_loader(
self,
param: nn.Parameter,
loaded_weight: torch.Tensor,
weight_name: str,
expert_id: int,
):
tp_rank = get_tensor_model_parallel_rank()
param_data = param.data
shard_size = self.intermediate_size
shard = slice(tp_rank * shard_size, (tp_rank + 1) * shard_size)
if weight_name.endswith("w1.weight"):
param_data[expert_id, 0:shard_size, :] = loaded_weight[shard, :]
if weight_name.endswith("w3.weight"):
param_data[expert_id, shard_size : 2 * shard_size, :] = loaded_weight[
shard, :
]
if weight_name.endswith("w2.weight"):
param_data[expert_id, :, :] = loaded_weight[:, shard]
if "act_scale" in weight_name or "weight_scale" in weight_name:
param_data[expert_id] = loaded_weight
def process_weights_after_loading(self):
# Fp8 is the only case where we need to process after loading.
if not self.use_fp8:
return
# If checkpoint is fp16, quantize here.
if not self.quant_config.is_checkpoint_fp8_serialized:
w13_weight = torch.empty_like(
self.w13_weight.data, dtype=torch.float8_e4m3fn
)
w2_weight = torch.empty_like(self.w2_weight.data, dtype=torch.float8_e4m3fn)
for expert in range(self.num_total_experts):
w13_weight[expert, :, :], self.w13_scale[expert] = ops.scaled_fp8_quant(
self.w13_weight.data[expert, :, :]
)
w2_weight[expert, :, :], self.w2_scale[expert] = ops.scaled_fp8_quant(
self.w2_weight.data[expert, :, :]
)
self.w13_weight = nn.Parameter(w13_weight, requires_grad=False)
self.w2_weight = nn.Parameter(w2_weight, requires_grad=False)
# If checkpoint is fp8 + static, cleanup act_scales.
# Since state_dict has an act_scale per expert but our kernels
# are passed one act_scale shared across all experts.
elif self.quant_config.activation_scheme == "static":
if self.a13_scale is None or self.a2_scale is None:
raise ValueError(
"QuantConfig has static quantization, but found "
"activation scales are None."
)
if not all_close_1d(self.a13_scale) or not all_close_1d(self.a2_scale):
print_warning_once(
"Found act_scales that are not equal for fp8 MoE layer. "
"Using the maximum across experts for each layer. "
)
self.a13_scale = nn.Parameter(self.a13_scale.max(), requires_grad=False)
self.a2_scale = nn.Parameter(self.a2_scale.max(), requires_grad=False)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
num_tokens, hidden_size = hidden_states.shape
# NOTE: hidden_states can have either 1D or 2D shape.
orig_shape = hidden_states.shape
hidden_states = hidden_states.view(-1, self.hidden_size)
# router_logits: (num_tokens, n_experts)
router_logits, _ = self.gate(hidden_states)
final_hidden_states = fused_moe(
hidden_states,
self.w13_weight,
self.w2_weight,
router_logits,
self.top_k,
renormalize=True,
inplace=True,
use_fp8=self.use_fp8,
w1_scale=self.w13_scale,
w2_scale=self.w2_scale,
a1_scale=self.a13_scale,
a2_scale=self.a2_scale,
)
if self.tp_size > 1:
final_hidden_states = tensor_model_parallel_all_reduce(final_hidden_states)
return final_hidden_states.view(num_tokens, hidden_size)
final_hidden_states = self.experts(hidden_states, router_logits)
return final_hidden_states.view(orig_shape)
class MixtralAttention(nn.Module):
@@ -291,7 +110,7 @@ class MixtralAttention(nn.Module):
max_position: int = 4096 * 32,
rope_theta: float = 10000,
quant_config: Optional[QuantizationConfig] = None,
sliding_window: Optional[int] = None,
prefix: str = "",
) -> None:
super().__init__()
self.hidden_size = hidden_size
@@ -314,7 +133,6 @@ class MixtralAttention(nn.Module):
self.kv_size = self.num_kv_heads * self.head_dim
self.scaling = self.head_dim**-0.5
self.rope_theta = rope_theta
self.sliding_window = sliding_window
self.qkv_proj = QKVParallelLinear(
hidden_size,
@@ -323,12 +141,14 @@ class MixtralAttention(nn.Module):
self.total_num_kv_heads,
bias=False,
quant_config=quant_config,
prefix=f"{prefix}.qkv_proj",
)
self.o_proj = RowParallelLinear(
self.total_num_heads * self.head_dim,
hidden_size,
bias=False,
quant_config=quant_config,
prefix=f"{prefix}.o_proj",
)
self.rotary_emb = get_rope(
self.head_dim,
@@ -365,6 +185,7 @@ class MixtralDecoderLayer(nn.Module):
config: MixtralConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.hidden_size = config.hidden_size
@@ -377,8 +198,8 @@ class MixtralDecoderLayer(nn.Module):
num_kv_heads=config.num_key_value_heads,
layer_id=layer_id,
rope_theta=rope_theta,
sliding_window=config.sliding_window,
quant_config=quant_config,
prefix=f"{prefix}.self_attn",
)
self.block_sparse_moe = MixtralMoE(
num_experts=config.num_local_experts,
@@ -386,6 +207,7 @@ class MixtralDecoderLayer(nn.Module):
hidden_size=config.hidden_size,
intermediate_size=config.intermediate_size,
quant_config=quant_config,
prefix=f"{prefix}.block_sparse_moe",
)
self.input_layernorm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
self.post_attention_layernorm = RMSNorm(
@@ -422,6 +244,7 @@ class MixtralModel(nn.Module):
self,
config: MixtralConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.padding_idx = config.pad_token_id
@@ -431,10 +254,11 @@ class MixtralModel(nn.Module):
config.vocab_size,
config.hidden_size,
)
# config.num_hidden_layers=16
self.layers = nn.ModuleList(
[
MixtralDecoderLayer(config, i, quant_config=quant_config)
MixtralDecoderLayer(
config, i, quant_config=quant_config, prefix=f"{prefix}.layers"
)
for i in range(config.num_hidden_layers)
]
)
@@ -462,6 +286,7 @@ class MixtralModel(nn.Module):
class MixtralForCausalLM(nn.Module):
def __init__(
self,
config: MixtralConfig,
@@ -471,11 +296,10 @@ class MixtralForCausalLM(nn.Module):
super().__init__()
self.config = config
self.quant_config = quant_config
self.model = MixtralModel(config, quant_config=quant_config)
self.model = MixtralModel(config, quant_config=quant_config, prefix="model")
self.lm_head = ParallelLMHead(config.vocab_size, config.hidden_size)
self.logits_processor = LogitsProcessor(config)
@torch.no_grad()
def forward(
self,
input_ids: torch.Tensor,
@@ -496,40 +320,13 @@ class MixtralForCausalLM(nn.Module):
("qkv_proj", "v_proj", "v"),
]
expert_params_mapping = (
[
# These are the weight scales for the experts
# (param_name, weight_name, expert_id)
(
"w13_scale" if weight_name in ["w1", "w3"] else "w2_scale",
f"experts.{expert_id}.{weight_name}.weight_scale",
expert_id,
)
for expert_id in range(self.config.num_local_experts)
for weight_name in ["w1", "w2", "w3"]
]
+ [
# These are the weights for the experts
# (param_name, weight_name, expert_id)
(
"w13_weight" if weight_name in ["w1", "w3"] else "w2_weight",
f"experts.{expert_id}.{weight_name}.weight",
expert_id,
)
for expert_id in range(self.config.num_local_experts)
for weight_name in ["w1", "w2", "w3"]
]
+ [
# These are the activation scales for the experts
# (param_name, weight_name, expert_id)
(
"a13_scale" if weight_name in ["w1", "w3"] else "a2_scale",
f"experts.{expert_id}.{weight_name}.act_scale",
expert_id,
)
for expert_id in range(self.config.num_local_experts)
for weight_name in ["w1", "w2", "w3"]
]
# Params for weights, fp8 weight scales, fp8 activation scales
# (param_name, weight_name, expert_id, shard_id)
expert_params_mapping = FusedMoE.make_expert_params_mapping(
ckpt_gate_proj_name="w1",
ckpt_down_proj_name="w2",
ckpt_up_proj_name="w3",
num_experts=self.config.num_local_experts,
)
params_dict = dict(self.named_parameters())
@@ -544,25 +341,35 @@ class MixtralForCausalLM(nn.Module):
# Skip loading extra bias for GPTQ models.
if name.endswith(".bias") and name not in params_dict:
continue
param = params_dict[name]
weight_loader = param.weight_loader
weight_loader(param, loaded_weight, shard_id)
break
else:
for param_name, weight_name, expert_id in expert_params_mapping:
for mapping in expert_params_mapping:
param_name, weight_name, expert_id, shard_id = mapping
if weight_name not in name:
continue
name = name.replace(weight_name, param_name)
param = params_dict[name]
weight_loader = param.weight_loader
weight_loader(
param, loaded_weight, weight_name, expert_id=expert_id
param,
loaded_weight,
weight_name,
shard_id=shard_id,
expert_id=expert_id,
)
break
else:
# Skip loading extra bias for GPTQ models.
if name.endswith(".bias") and name not in params_dict:
continue
if name is None:
continue
param = params_dict[name]
weight_loader = getattr(
param, "weight_loader", default_weight_loader
@@ -570,9 +377,4 @@ class MixtralForCausalLM(nn.Module):
weight_loader(param, loaded_weight)
def all_close_1d(x: torch.Tensor) -> bool:
assert len(x.shape) == 1
return all(torch.allclose(x[0], x[i]) for i in range(x.shape[0]))
EntryClass = MixtralForCausalLM

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@@ -160,7 +160,6 @@ class MixtralAttention(nn.Module):
max_position: int = 4096 * 32,
rope_theta: float = 10000,
quant_config: Optional[QuantizationConfig] = None,
sliding_window: Optional[int] = None,
) -> None:
super().__init__()
self.hidden_size = hidden_size
@@ -183,7 +182,6 @@ class MixtralAttention(nn.Module):
self.kv_size = self.num_kv_heads * self.head_dim
self.scaling = self.head_dim**-0.5
self.rope_theta = rope_theta
self.sliding_window = sliding_window
self.qkv_proj = QKVParallelLinear(
hidden_size,
@@ -246,7 +244,6 @@ class MixtralDecoderLayer(nn.Module):
num_kv_heads=config.num_key_value_heads,
layer_id=layer_id,
rope_theta=rope_theta,
sliding_window=config.sliding_window,
quant_config=quant_config,
)
self.block_sparse_moe = MixtralMoE(config=config, quant_config=quant_config)