Files
FastDeploy/fastdeploy/model_executor/layers/quantization/w4afp8.py
2025-06-29 23:29:37 +00:00

99 lines
3.2 KiB
Python

"""
# Copyright (c) 2025 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
from typing import Optional
import paddle
import fastdeploy
from .quant_base import QuantConfigBase, QuantMethodBase
QUANT_SCALING_FACTOR = 448
class W4AFP8Config(QuantConfigBase):
"""
quantization config for weight 4bits and activation fp8
"""
def __init__(self, weight_scale_dict, act_scale_dict) -> None:
super().__init__()
self.weight_scale_dict = weight_scale_dict
self.act_scale_dict = act_scale_dict
self.quant_max_bound = 448
self.quant_min_bound = -448
self.quant_round_type = 1
def name(self) -> str:
return "w4afp8"
@classmethod
def from_config(cls, config: dict) -> "W4AFP8Config":
weight_scale_dict = config["weight_scale_dict"]
act_scale_dict = config["act_scale_dict"]
return cls(weight_scale_dict, act_scale_dict)
def get_quant_method(self, layer) -> Optional[QuantMethodBase]:
return W4AFP8LinearMethod(self)
class W4AFP8LinearMethod(QuantMethodBase):
"""
W4 AFP8 quant method for linear
"""
def __init__(
self,
quant_config: W4AFP8Config,
) -> None:
super().__init__()
self.quant_config = quant_config
def create_weights(self, layer):
layer.linear_weight_shape.reverse()
layer.linear_weight_shape[0] //= 2
layer.weight_dtype = "int8"
pass
def process_loaded_weights(self, layer, weights) -> None:
quanted_weight_tensor, weight_scale_tensor = (
fastdeploy.model_executor.ops.gpu.
scaled_gemm_f8_i4_f16_weight_quantize(
paddle.cast(weights, "float32").cpu(),
groupsize=-1,
scale_dtype="float16",
))
weight_scale_tensor = paddle.view(weight_scale_tensor, layer._dtype)
layer.linear_weight.set_value(quanted_weight_tensor)
layer.linear_weight_scale.set_value(weight_scale_tensor)
def apply(self, layer, x):
linear_out = fastdeploy.model_executor.ops.gpu.scaled_gemm_f8_i4_f16(
x,
layer.linear_weight,
layer.linear_weight_scale,
zero_points=None,
bias=layer.linear_bias if layer.add_bias else None,
out_scale=self.quant_config.weight_scale_dict.get(layer.prefix +
".weight_scale")
/ (self.quant_config.act_scale_dict.get(layer.prefix +
".activation_scale") *
QUANT_SCALING_FACTOR * QUANT_SCALING_FACTOR),
groupsize=0,
out_dtype=layer._dtype,
)
return linear_out