hf_text-generation-inference/server/text_generation_server/layers/exl2.py

84 lines
2.5 KiB
Python

import torch
from typing import List, Union
from dataclasses import dataclass
from text_generation_server.utils.weights import WeightsLoader, Weights
@dataclass
class Exl2Weight:
"""
Exllama2 exl2 quantized weights.
"""
q_weight: torch.Tensor
q_scale: torch.Tensor
q_invperm: torch.Tensor
q_scale_max: torch.Tensor
q_groups: torch.Tensor
def __post_init__(self):
self.q_scale_max /= 256
self.q_invperm = self.q_invperm.short()
@property
def device(self) -> torch.device:
return self.q_weight.device
class Exl2WeightsLoader(WeightsLoader):
"""Loader for exl2-quantized weights."""
def get_weights_col_packed(
self,
weights: Weights,
prefix: str,
block_sizes: Union[int, List[int]],
):
raise RuntimeError("Column-packed weights are not supported for exl")
def get_weights_col(self, weights: Weights, prefix: str):
try:
q_weight = weights.get_tensor(f"{prefix}.q_weight")
except RuntimeError:
raise RuntimeError(
"Cannot load `exl2`-quantized weight, make sure the model is already quantized."
)
q_scale = weights.get_tensor(f"{prefix}.q_scale")
q_invperm = weights.get_tensor(f"{prefix}.q_invperm")
q_scale_max = weights.get_tensor(f"{prefix}.q_scale_max")
q_groups = weights.get_tensor(f"{prefix}.q_groups")
return Exl2Weight(
q_weight=q_weight,
q_scale=q_scale,
q_invperm=q_invperm,
q_scale_max=q_scale_max,
q_groups=q_groups,
)
def get_multi_weights_col(self, weights: Weights, prefixes: List[str], dim: int):
raise ValueError("get_multi_weights_col is not supported for exl2")
def get_weights_row(self, weights: Weights, prefix: str):
try:
q_weight = weights.get_tensor(f"{prefix}.q_weight")
except RuntimeError:
raise RuntimeError(
"Cannot load `exl2`-quantized weight, make sure the model is already quantized."
)
q_scale = weights.get_tensor(f"{prefix}.q_scale")
q_invperm = weights.get_tensor(f"{prefix}.q_invperm")
q_scale_max = weights.get_tensor(f"{prefix}.q_scale_max")
q_groups = weights.get_tensor(f"{prefix}.q_groups")
return Exl2Weight(
q_weight=q_weight,
q_scale=q_scale,
q_invperm=q_invperm,
q_scale_max=q_scale_max,
q_groups=q_groups,
)