ColossalAI/applications/Chat/coati/models/bloom/bloom_rm.py

37 lines
1.0 KiB
Python

from typing import Optional
import torch.nn as nn
from transformers import BloomConfig, BloomModel
from ..base import RewardModel
class BLOOMRM(RewardModel):
"""
BLOOM Reward model.
Args:
pretrained (str): Pretrained model name or path.
config (BloomConfig): Model config.
lora_rank (int): LoRA rank.
lora_train_bias (str): LoRA bias training mode.
"""
def __init__(
self,
pretrained: str = None,
config: Optional[BloomConfig] = None,
lora_rank: int = 0,
lora_train_bias: str = "none",
) -> None:
if pretrained is not None:
model = BloomModel.from_pretrained(pretrained)
elif config is not None:
model = BloomModel(config)
else:
model = BloomModel(BloomConfig())
value_head = nn.Linear(model.config.hidden_size, 1)
value_head.weight.data.normal_(mean=0.0, std=1 / (model.config.hidden_size + 1))
super().__init__(model, value_head, lora_rank, lora_train_bias)