Files
sglang/python/sglang/srt/layers/quantization/gptq.py
2025-07-01 22:34:43 -07:00

736 lines
26 KiB
Python

import logging
from fractions import Fraction
from typing import Any, Callable, Dict, List, Optional, Union
import torch
from sglang.srt.layers.linear import LinearBase, set_weight_attrs
from sglang.srt.layers.quantization.base_config import (
QuantizationConfig,
QuantizeMethodBase,
)
from sglang.srt.layers.quantization.utils import replace_parameter
from sglang.srt.utils import is_cuda
_is_cuda = is_cuda()
try:
from vllm import _custom_ops as ops
from vllm.model_executor.layers.quantization.gptq import GPTQLinearMethod
from vllm.model_executor.layers.quantization.gptq_marlin import (
FusedMoE,
FusedMoEMethodBase,
FusedMoeWeightScaleSupported,
GPTQMarlinLinearMethod,
marlin_moe_permute_scales,
)
from vllm.model_executor.layers.quantization.marlin import MarlinLinearMethod
from vllm.model_executor.layers.quantization.utils.marlin_utils import (
check_marlin_supported,
)
from vllm.scalar_type import scalar_types
VLLM_AVAILABLE = True
except ImportError:
VLLM_AVAILABLE = False
GPTQLinearMethod = MarlinLinearMethod = Any
FusedMoEMethodBase = QuantizeMethodBase
class scalar_types:
uint4b8 = "uint4b8"
uint8b128 = "uint8b128"
logger = logging.getLogger(__name__)
def check_marlin_format(hf_quant_cfg: Dict[str, Any]) -> bool:
# compat: gptqmodel and autogptq (eol) main use checkpoint_format: str
# compat: autogptq <=0.7.1 is_marlin_format: bool
return hf_quant_cfg.get("checkpoint_format") == "marlin" or hf_quant_cfg.get(
"is_marlin_format", False
)
class GPTQConfig(QuantizationConfig):
"""Config class for GPTQ.
Reference: https://arxiv.org/abs/2210.17323
"""
def __init__(
self,
weight_bits: int,
group_size: int,
desc_act: bool,
lm_head_quantized: bool,
dynamic: Dict[str, Dict[str, Union[int, bool]]],
) -> None:
# GPTQModel use `dynamic` config property to allow per module
# quantization config so each module can be individually optimized.
# Format is Dict[str, Dict] where key is a regex string that can
# perform both positive ("+:" prefixed) or negative ("-:" prefixed)
# matching of a module.
# Default to positive match, override base quant config mode, if no
# prefix is used. Value is in dict format of field key and override
# value.
# Negative matching will skip quantization init for this module
# entirely:
# non-quantized inference. More details and quantization examples can be
# found at: https://github.com/ModelCloud/GPTQModel
# Example:
# # last 1/2 of the layers 10-21 has 8bit vs 4bit for 0-9
# # last 1/4 of the layers 16-21 has 8bit and group_size 64
# dynamic = {
# #`.*\.` matches the layers_node prefix
# # positive match layer 10-15
# r"+:.*\.(?:1[0-5])\..*": {"bits": 8,},
# # positive match layer 16-21
# r"+:.*\.(?:1[6-9]|20|21)\..*": {"bits": 8, "group_size": 64,},
# r"-:.*\.moe\..*": {}, # negative match (skip) all `moe` layers
# }
super().__init__()
self.dynamic = dynamic
self.weight_bits = weight_bits
self.group_size = group_size
self.desc_act = desc_act
self.lm_head_quantized = lm_head_quantized
self.pack_factor = Fraction(32, self.weight_bits)
if self.weight_bits not in [2, 3, 4, 8]:
raise ValueError(
"Currently, only 2/3/4/8-bit weight quantization is "
f"supported for GPTQ, but got {self.weight_bits} bits."
)
def __repr__(self) -> str:
return (
f"GPTQConfig(weight_bits={self.weight_bits}, "
f"group_size={self.group_size}, "
f"desc_act={self.desc_act}),"
f"lm_head_quantized={self.lm_head_quantized}), "
f"dynamic={self.dynamic}"
)
def get_scaled_act_names(self) -> List[str]:
"""Returns the activation function names that should be post-scaled.
For now, this is only used by AWQ.
"""
raise NotImplementedError
@classmethod
def get_name(cls) -> str:
return "gptq"
@classmethod
def get_supported_act_dtypes(cls) -> List[torch.dtype]:
return [torch.half]
@classmethod
# Need to figure it out
def get_min_capability(cls) -> int:
return 60
@classmethod
def get_config_filenames(cls) -> List[str]:
return ["quantize_config.json"]
@classmethod
def from_config(cls, config: Dict[str, Any]) -> "GPTQConfig":
dynamic = cls.get_from_keys_or(config, ["dynamic"], default={})
dynamic = {} if dynamic is None else dynamic
weight_bits = cls.get_from_keys(config, ["bits"])
group_size = cls.get_from_keys(config, ["group_size"])
desc_act = cls.get_from_keys(config, ["desc_act"])
lm_head_quantized = cls.get_from_keys_or(config, ["lm_head"], default=False)
return cls(weight_bits, group_size, desc_act, lm_head_quantized, dynamic)
def get_quant_method(
self, layer: torch.nn.Module, prefix: str
) -> Optional[GPTQLinearMethod]:
# Delay the import to avoid circular dependency
from sglang.srt.layers.quantization import get_linear_quant_method
return get_linear_quant_method(self, layer, prefix, GPTQLinearMethod)
class GPTQMarlinConfig(QuantizationConfig):
"""Config class for GPTQ Marlin"""
# (num_bits, is_sym) -> quant_type
TYPE_MAP = {
(4, True): scalar_types.uint4b8,
(8, True): scalar_types.uint8b128,
}
def __init__(
self,
weight_bits: int,
group_size: int,
desc_act: bool,
is_sym: bool,
lm_head_quantized: bool,
dynamic: Dict[str, Dict[str, Union[int, bool]]],
full_config: Dict[str, Any],
) -> None:
super().__init__()
if desc_act and group_size == -1:
# In this case, act_order == True is the same as act_order == False
# (since we have only one group per output channel)
desc_act = False
# GPTQModel use `dynamic` config property to allow per module
# quantization config so each module can be individually optimized.
# Format is Dict[str, Dict] where key is a regex string that can
# perform both positive ("+:" prefixed) or negative ("-:" prefixed)
# matching of a module.
# Default to positive match, override base quant config mode, if no
# prefix is used. Value is in dict format of field key and override
# value.
# Negative matching will skip quantization init for this module
# entirely:
# non-quantized inference. More details and quantization examples can be
# found at: https://github.com/ModelCloud/GPTQModel
# Example:
# # last 1/2 of the layers 10-21 has 8bit vs 4bit for 0-9
# # last 1/4 of the layers 16-21 has 8bit and group_size 64
# dynamic = {
# #`.*\.` matches the layers_node prefix
# # positive match layer 10-15
# r"+:.*\.(?:1[0-5])\..*": {"bits": 8,},
# # positive match layer 16-21
# r"+:.*\.(?:1[6-9]|20|21)\..*": {"bits": 8, "group_size": 64,},
# r"-:.*\.moe\..*": {}, # negative match (skip) all `moe` layers
# }
self.dynamic = dynamic
self.weight_bits = weight_bits
self.is_sym = is_sym
self.pack_factor = 32 // weight_bits # packed into int32
self.group_size = group_size
self.desc_act = desc_act
self.lm_head_quantized = lm_head_quantized
self.full_config = full_config
if (weight_bits, is_sym) not in self.TYPE_MAP:
raise ValueError(
"Unsupported quantization config: " f"bits={weight_bits}, sym={is_sym}"
)
# (num_bits, is_sym) -> quant_type
self.quant_type = self.TYPE_MAP[(weight_bits, is_sym)]
def __repr__(self) -> str:
return (
f"GPTQMarlinConfig(quant_type={self.quant_type}, "
f"group_size={self.group_size}, "
f"desc_act={self.desc_act}, "
f"lm_head_quantized={self.lm_head_quantized}), "
f"dynamic={self.dynamic}"
)
def get_scaled_act_names(self) -> List[str]:
"""Returns the activation function names that should be post-scaled.
For now, this is only used by AWQ.
"""
raise NotImplementedError
@classmethod
def get_name(cls) -> str:
return "gptq_marlin"
@classmethod
def get_supported_act_dtypes(cls) -> List[torch.dtype]:
return [torch.half, torch.bfloat16]
@classmethod
def get_min_capability(cls) -> int:
return 80
@classmethod
def get_config_filenames(cls) -> List[str]:
return ["quantize_config.json"]
@classmethod
def from_config(cls, config: Dict[str, Any]) -> "GPTQMarlinConfig":
dynamic = cls.get_from_keys_or(config, ["dynamic"], default={})
dynamic = {} if dynamic is None else dynamic
weight_bits = cls.get_from_keys(config, ["bits"])
group_size = cls.get_from_keys(config, ["group_size"])
desc_act = cls.get_from_keys(config, ["desc_act"])
is_sym = cls.get_from_keys(config, ["sym"])
lm_head_quantized = cls.get_from_keys_or(config, ["lm_head"], default=False)
return cls(
weight_bits,
group_size,
desc_act,
is_sym,
lm_head_quantized,
dynamic,
config,
)
@classmethod
def override_quantization_method(cls, hf_quant_cfg, user_quant) -> Optional[str]:
is_marlin_format = check_marlin_format(hf_quant_cfg)
can_convert = cls.is_gptq_marlin_compatible(hf_quant_cfg)
is_valid_user_quant = (
user_quant is None or user_quant == "marlin" or user_quant == "gptq_marlin"
)
if not is_marlin_format and can_convert and is_valid_user_quant:
msg = (
"The model is convertible to {} during runtime."
" Using {} kernel.".format(cls.get_name(), cls.get_name())
)
logger.info(msg)
return cls.get_name()
if not is_marlin_format and can_convert and user_quant == "gptq":
logger.info(
"Detected that the model can run with gptq_marlin"
", however you specified quantization=gptq explicitly,"
" so forcing gptq. Use quantization=gptq_marlin for"
" faster inference"
)
return None
def get_quant_method(
self, layer: torch.nn.Module, prefix: str
) -> Optional[QuantizeMethodBase]:
# Delay the import to avoid circular dependency
from sglang.srt.layers.moe.fused_moe_triton import FusedMoE
from sglang.srt.layers.quantization import get_linear_quant_method
if isinstance(layer, FusedMoE):
return GPTQMarlinMoEMethod(self)
# TODO: re-enable after SGLang syncs with vllm >= 0.7.3
# if layer.num_experts > 32:
# # For MoEs with many experts the moe_wna16 kernel is faster
# return MoeWNA16Config.from_config(self.full_config).get_quant_method(
# layer, prefix
# )
# else:
# return GPTQMarlinMoEMethod(self)
return get_linear_quant_method(self, layer, prefix, GPTQMarlinLinearMethod)
@classmethod
def is_gptq_marlin_compatible(cls, quant_config: Dict[str, Any]):
quant_method = quant_config.get("quant_method", "").lower()
num_bits = quant_config.get("bits")
group_size = quant_config.get("group_size")
sym = quant_config.get("sym")
desc_act = quant_config.get("desc_act")
if not _is_cuda:
return False
if quant_method != "gptq":
return False
# Marlin conversion is only valid if required properties are found
if num_bits is None or group_size is None or sym is None or desc_act is None:
return False
if (num_bits, sym) not in cls.TYPE_MAP:
return False
assert (
VLLM_AVAILABLE
), "vllm is not installed, to use gptq_marlin, please install vllm"
return check_marlin_supported(
quant_type=cls.TYPE_MAP[(num_bits, sym)], group_size=group_size
)
class MarlinConfig(QuantizationConfig):
"""Config class for Marlin.
Reference: https://github.com/IST-DASLab/marlin/tree/master
"""
def __init__(
self,
group_size: int,
lm_head_quantized: bool,
) -> None:
# Group size for the quantization.
self.group_size = group_size
self.lm_head_quantized = lm_head_quantized
if self.group_size != 128 and self.group_size != -1:
raise ValueError(
"Currently, only group size 128 and -1 (channelwise) "
"is supported for Marlin, but got group_size of "
f"{self.group_size}"
)
# 4 Bits packed into 32 bit datatype.
self.pack_factor = 32 // 4
# Tile size used by marlin kernels.
self.tile_size = 16
# Min out_features dim
self.min_n_threads = 64
# Min in_features dim
self.min_k_threads = 128
# Max parallel problems to solve at once (improves large
# batch performance)
self.max_parallel = 16
# Permutation length used by the marlin kernels.
self.perm_len = 1024
def __repr__(self) -> str:
return (
f"MarlinConfig(group_size={self.group_size}, "
f"lm_head_quantized={self.lm_head_quantized})"
)
@classmethod
def get_name(cls) -> str:
return "marlin"
@classmethod
def get_supported_act_dtypes(cls) -> List[torch.dtype]:
return [torch.half]
@classmethod
# Need to figure it out
def get_min_capability(cls) -> int:
return 80
@classmethod
def get_config_filenames(cls) -> List[str]:
return ["quantize_config.json"]
@classmethod
def from_config(cls, config: Dict[str, Any]) -> "MarlinConfig":
group_size = cls.get_from_keys(config, ["group_size"])
lm_head_quantized = cls.get_from_keys_or(config, ["lm_head"], default=False)
return cls(group_size, lm_head_quantized)
@classmethod
def override_quantization_method(cls, hf_quant_cfg, user_quant) -> Optional[str]:
is_marlin_format = check_marlin_format(hf_quant_cfg)
is_valid_user_quant = (
user_quant is None or user_quant == "gptq" or user_quant == "marlin"
)
if is_marlin_format and is_valid_user_quant:
msg = "The model is serialized in {} format. Using {} kernel.".format(
cls.get_name(), cls.get_name()
)
logger.info(msg)
return cls.get_name()
return None
def get_quant_method(
self, layer: torch.nn.Module, prefix: str
) -> Optional[MarlinLinearMethod]:
# Delay the import to avoid circular dependency
from sglang.srt.layers.vocab_parallel_embedding import ParallelLMHead
if isinstance(layer, LinearBase) or (
isinstance(layer, ParallelLMHead) and self.lm_head_quantized
):
return MarlinLinearMethod(self)
return None
class GPTQMarlinMoEMethod(FusedMoEMethodBase):
"""MoE Marlin method with quantization."""
def __init__(self, quant_config: GPTQMarlinConfig) -> None:
self.quant_config = quant_config
def create_weights(
self,
layer: torch.nn.Module,
num_experts: int,
hidden_size: int,
intermediate_size_per_partition: int,
params_dtype: torch.dtype,
**extra_weight_attrs,
):
intermediate_size = extra_weight_attrs.pop("intermediate_size")
self.is_k_full = (not self.quant_config.desc_act) or (
intermediate_size_per_partition == intermediate_size
)
if self.quant_config.group_size != -1:
scales_size13 = hidden_size // self.quant_config.group_size
w2_scales_size = (
intermediate_size
if self.quant_config.desc_act
else intermediate_size_per_partition
)
scales_size2 = w2_scales_size // self.quant_config.group_size
strategy = FusedMoeWeightScaleSupported.GROUP.value
else:
scales_size13 = 1
scales_size2 = 1
strategy = FusedMoeWeightScaleSupported.CHANNEL.value
extra_weight_attrs.update({"quant_method": strategy, "is_transposed": True})
# Fused gate_up_proj (column parallel)
w13_qweight = torch.nn.Parameter(
torch.empty(
num_experts,
hidden_size // self.quant_config.pack_factor,
2 * intermediate_size_per_partition,
dtype=torch.int32,
),
requires_grad=False,
)
layer.register_parameter("w13_qweight", w13_qweight)
set_weight_attrs(w13_qweight, extra_weight_attrs)
# down_proj (row parallel)
w2_qweight = torch.nn.Parameter(
torch.empty(
num_experts,
intermediate_size_per_partition // self.quant_config.pack_factor,
hidden_size,
dtype=torch.int32,
),
requires_grad=False,
)
layer.register_parameter("w2_qweight", w2_qweight)
set_weight_attrs(w2_qweight, extra_weight_attrs)
# up_proj scales
w13_scales = torch.nn.Parameter(
torch.empty(
num_experts,
scales_size13,
2 * intermediate_size_per_partition,
dtype=torch.half,
),
requires_grad=False,
)
layer.register_parameter("w13_scales", w13_scales)
set_weight_attrs(w13_scales, extra_weight_attrs)
# down_proj scales
w2_scales = torch.nn.Parameter(
torch.empty(num_experts, scales_size2, hidden_size, dtype=torch.half),
requires_grad=False,
)
layer.register_parameter("w2_scales", w2_scales)
set_weight_attrs(w2_scales, extra_weight_attrs)
# dont shard the w2 scales when running act order
set_weight_attrs(w2_scales, {"load_full_w2": self.quant_config.desc_act})
# up_proj scales
w13_qzeros = torch.nn.Parameter(
torch.empty(
num_experts,
scales_size13,
2 * intermediate_size_per_partition // self.quant_config.pack_factor,
dtype=params_dtype,
),
requires_grad=False,
)
layer.register_parameter("w13_qzeros", w13_qzeros)
set_weight_attrs(w13_qzeros, extra_weight_attrs)
# down_proj scales
w2_qzeros = torch.nn.Parameter(
torch.empty(
num_experts,
scales_size2,
hidden_size // self.quant_config.pack_factor,
dtype=params_dtype,
),
requires_grad=False,
)
layer.register_parameter("w2_qzeros", w2_qzeros)
set_weight_attrs(w2_qzeros, extra_weight_attrs)
# dont shard the w2 scales when running act order
set_weight_attrs(w2_qzeros, {"load_full_w2": self.quant_config.desc_act})
w13_g_idx = torch.nn.Parameter(
torch.empty(
num_experts,
hidden_size,
dtype=torch.int32,
),
requires_grad=False,
)
layer.register_parameter("w13_g_idx", w13_g_idx)
set_weight_attrs(w13_g_idx, extra_weight_attrs)
w2_g_idx = torch.nn.Parameter(
torch.empty(
num_experts,
intermediate_size_per_partition,
dtype=torch.int32,
),
requires_grad=False,
)
layer.register_parameter("w2_g_idx", w2_g_idx)
set_weight_attrs(w2_g_idx, extra_weight_attrs)
w13_g_idx_sort_indices = torch.nn.Parameter(
torch.empty(
num_experts,
hidden_size,
dtype=torch.int32,
),
requires_grad=False,
)
layer.register_parameter("w13_g_idx_sort_indices", w13_g_idx_sort_indices)
set_weight_attrs(w13_g_idx_sort_indices, extra_weight_attrs)
w2_g_idx_sort_indices = torch.nn.Parameter(
torch.empty(
num_experts,
intermediate_size_per_partition,
dtype=torch.int32,
),
requires_grad=False,
)
layer.register_parameter("w2_g_idx_sort_indices", w2_g_idx_sort_indices)
set_weight_attrs(w2_g_idx_sort_indices, extra_weight_attrs)
def process_weights_after_loading(self, layer: torch.nn.Module) -> None:
# Process act_order
if self.quant_config.desc_act:
# Get sorting based on g_idx
num_experts = layer.w13_g_idx.shape[0]
w13_g_idx_sort_indices = torch.empty_like(layer.w13_g_idx)
w2_g_idx_sort_indices = torch.empty_like(layer.w2_g_idx)
w13_sorted_g_idx = torch.empty_like(layer.w13_g_idx)
w2_sorted_g_idx = torch.empty_like(layer.w2_g_idx)
for e in range(num_experts):
w13_g_idx_sort_indices[e] = torch.argsort(layer.w13_g_idx[e]).to(
torch.int32
)
w2_g_idx_sort_indices[e] = torch.argsort(layer.w2_g_idx[e]).to(
torch.int32
)
w13_sorted_g_idx[e] = layer.w13_g_idx[e][w13_g_idx_sort_indices[e]]
w2_sorted_g_idx[e] = layer.w2_g_idx[e][w2_g_idx_sort_indices[e]]
replace_parameter(layer, "w13_g_idx", w13_sorted_g_idx)
replace_parameter(layer, "w2_g_idx", w2_sorted_g_idx)
replace_parameter(layer, "w13_g_idx_sort_indices", w13_g_idx_sort_indices)
replace_parameter(layer, "w2_g_idx_sort_indices", w2_g_idx_sort_indices)
else:
# Reset g_idx related tensors
num_experts = layer.w13_g_idx.shape[0]
device = layer.w13_g_idx.device
layer.w13_g_idx = torch.nn.Parameter(
torch.empty((num_experts, 0), dtype=torch.int32, device=device),
requires_grad=False,
)
layer.w2_g_idx = torch.nn.Parameter(
torch.empty((num_experts, 0), dtype=torch.int32, device=device),
requires_grad=False,
)
layer.w13_g_idx_sort_indices = torch.nn.Parameter(
torch.empty((num_experts, 0), dtype=torch.int32, device=device),
requires_grad=False,
)
layer.w2_g_idx_sort_indices = torch.nn.Parameter(
torch.empty((num_experts, 0), dtype=torch.int32, device=device),
requires_grad=False,
)
# Repack weights
marlin_w13_qweight = ops.gptq_marlin_moe_repack(
layer.w13_qweight,
layer.w13_g_idx_sort_indices,
layer.w13_qweight.shape[1] * self.quant_config.pack_factor,
layer.w13_qweight.shape[2],
self.quant_config.quant_type.size_bits,
)
replace_parameter(layer, "w13_qweight", marlin_w13_qweight)
marlin_w2_qweight = ops.gptq_marlin_moe_repack(
layer.w2_qweight,
layer.w2_g_idx_sort_indices,
layer.w2_qweight.shape[1] * self.quant_config.pack_factor,
layer.w2_qweight.shape[2],
self.quant_config.quant_type.size_bits,
)
replace_parameter(layer, "w2_qweight", marlin_w2_qweight)
# Repack scales
marlin_w13_scales = marlin_moe_permute_scales(
s=layer.w13_scales,
size_k=layer.intermediate_size_per_partition,
size_n=layer.w13_scales.shape[2],
group_size=self.quant_config.group_size,
)
replace_parameter(layer, "w13_scales", marlin_w13_scales)
marlin_w2_scales = marlin_moe_permute_scales(
s=layer.w2_scales,
size_k=layer.w2_scales.shape[1]
* (
self.quant_config.group_size
if self.quant_config.group_size != -1
else self.quant_config.pack_factor
),
size_n=layer.w2_scales.shape[2],
group_size=self.quant_config.group_size,
)
replace_parameter(layer, "w2_scales", marlin_w2_scales)
def apply(
self,
layer: torch.nn.Module,
x: torch.Tensor,
router_logits: torch.Tensor,
top_k: int,
renormalize: bool,
use_grouped_topk: bool = False,
topk_group: Optional[int] = None,
num_expert_group: Optional[int] = None,
global_num_experts: int = -1,
expert_map: Optional[torch.Tensor] = None,
custom_routing_function: Optional[Callable] = None,
scoring_func: str = "softmax",
e_score_correction_bias: Optional[torch.Tensor] = None,
activation: str = "silu",
) -> torch.Tensor:
assert activation == "silu", "Only SiLU activation is supported."
# The input must currently be float16
orig_dtype = x.dtype
x = x.half()
topk_weights, topk_ids = FusedMoE.select_experts(
hidden_states=x,
router_logits=router_logits,
use_grouped_topk=use_grouped_topk,
top_k=top_k,
renormalize=renormalize,
topk_group=topk_group,
num_expert_group=num_expert_group,
custom_routing_function=custom_routing_function,
scoring_func=scoring_func,
e_score_correction_bias=e_score_correction_bias,
)
return torch.ops.vllm.fused_marlin_moe(
x,
layer.w13_qweight,
layer.w2_qweight,
layer.w13_scales,
layer.w2_scales,
router_logits,
topk_weights,
topk_ids,
g_idx1=layer.w13_g_idx,
g_idx2=layer.w2_g_idx,
sort_indices1=layer.w13_g_idx_sort_indices,
sort_indices2=layer.w2_g_idx_sort_indices,
quant_type_id=self.quant_config.quant_type.id,
is_k_full=self.is_k_full,
).to(orig_dtype)