ColossalAI/applications/Chat/examples/train_reward_model.py

197 lines
8.8 KiB
Python

import argparse
from random import randint
import torch
import torch.distributed as dist
from coati.dataset import HhRlhfDataset, RmStaticDataset
from coati.models import LogExpLoss, LogSigLoss
from coati.models.bloom import BLOOMRM
from coati.models.gpt import GPTRM
from coati.models.llama import LlamaRM
from coati.models.opt import OPTRM
from coati.trainer import RewardModelTrainer
from coati.trainer.strategies import DDPStrategy, GeminiStrategy, LowLevelZeroStrategy
from datasets import load_dataset
from torch.optim import Adam
from torch.optim.lr_scheduler import CosineAnnealingLR
from torch.utils.data import DataLoader
from torch.utils.data.distributed import DistributedSampler
from transformers import AutoTokenizer, BloomTokenizerFast, LlamaTokenizer
from transformers.models.gpt2.tokenization_gpt2 import GPT2Tokenizer
from colossalai.nn.optimizer import HybridAdam
def train(args):
# configure strategy
if args.strategy == 'ddp':
strategy = DDPStrategy()
elif args.strategy == 'colossalai_gemini':
strategy = GeminiStrategy(placement_policy='cuda')
elif args.strategy == 'colossalai_zero2':
strategy = LowLevelZeroStrategy(stage=2, placement_policy='cuda')
else:
raise ValueError(f'Unsupported strategy "{args.strategy}"')
# configure model
with strategy.model_init_context():
if args.model == 'bloom':
model = BLOOMRM(pretrained=args.pretrain, lora_rank=args.lora_rank).to(torch.cuda.current_device())
elif args.model == 'opt':
model = OPTRM(pretrained=args.pretrain, lora_rank=args.lora_rank).to(torch.cuda.current_device())
elif args.model == 'gpt2':
model = GPTRM(pretrained=args.pretrain, lora_rank=args.lora_rank).to(torch.cuda.current_device())
elif args.model == 'llama':
model = LlamaRM(pretrained=args.pretrain, lora_rank=args.lora_rank).to(torch.cuda.current_device())
else:
raise ValueError(f'Unsupported model "{args.model}"')
if args.model_path is not None:
state_dict = torch.load(args.model_path)
model.load_state_dict(state_dict)
model = model.to(torch.float16)
# configure tokenizer
if args.model == 'gpt2':
tokenizer = GPT2Tokenizer.from_pretrained('gpt2')
tokenizer.pad_token = tokenizer.eos_token
elif args.model == 'bloom':
tokenizer = BloomTokenizerFast.from_pretrained('bigscience/bloom-560m')
tokenizer.pad_token = tokenizer.eos_token
elif args.model == 'opt':
tokenizer = AutoTokenizer.from_pretrained("facebook/opt-350m")
tokenizer.pad_token = tokenizer.eos_token
elif args.model == 'llama':
tokenizer = LlamaTokenizer.from_pretrained(args.pretrain)
tokenizer.pad_token = tokenizer.unk_token
else:
raise ValueError(f'Unsupported model "{args.model}"')
# configure optimizer
if args.strategy.startswith('colossalai'):
optim = HybridAdam(model.parameters(), lr=5e-6)
else:
optim = Adam(model.parameters(), lr=5e-6)
# configure loss function
if args.loss_fn == 'log_sig':
loss_fn = LogSigLoss()
elif args.loss_fn == 'log_exp':
loss_fn = LogExpLoss()
else:
raise ValueError(f'Unsupported loss function "{args.loss_fn}"')
# prepare for data and dataset
if args.subset is not None:
data = load_dataset(args.dataset, data_dir=args.subset)
else:
data = load_dataset(args.dataset)
if args.test:
train_data = data['train'].select(range(100))
eval_data = data['test'].select(range(10))
else:
train_data = data['train']
eval_data = data['test']
valid_data = data['test'].select((randint(0, len(eval_data) - 1) for _ in range(len(eval_data) // 5)))
if args.dataset == 'Dahoas/rm-static':
train_dataset = RmStaticDataset(train_data, tokenizer, args.max_len)
valid_dataset = RmStaticDataset(valid_data, tokenizer, args.max_len)
eval_dataset = RmStaticDataset(eval_data, tokenizer, args.max_len)
elif args.dataset == 'Anthropic/hh-rlhf':
train_dataset = HhRlhfDataset(train_data, tokenizer, args.max_len)
valid_dataset = HhRlhfDataset(valid_data, tokenizer, args.max_len)
eval_dataset = HhRlhfDataset(eval_data, tokenizer, args.max_len)
else:
raise ValueError(f'Unsupported dataset "{args.dataset}"')
if dist.is_initialized() and dist.get_world_size() > 1:
train_sampler = DistributedSampler(train_dataset,
shuffle=True,
seed=42,
drop_last=True,
rank=dist.get_rank(),
num_replicas=dist.get_world_size())
valid_sampler = DistributedSampler(valid_dataset,
shuffle=True,
seed=42,
drop_last=True,
rank=dist.get_rank(),
num_replicas=dist.get_world_size())
eval_sampler = DistributedSampler(eval_dataset,
shuffle=True,
seed=42,
drop_last=True,
rank=dist.get_rank(),
num_replicas=dist.get_world_size())
else:
train_sampler = None
valid_sampler = None
eval_sampler = None
train_dataloader = DataLoader(train_dataset,
shuffle=(train_sampler is None),
sampler=train_sampler,
batch_size=args.batch_size,
pin_memory=True)
valid_dataloader = DataLoader(valid_dataset,
shuffle=(valid_sampler is None),
sampler=valid_sampler,
batch_size=args.batch_size,
pin_memory=True)
eval_dataloader = DataLoader(eval_dataset,
shuffle=(eval_sampler is None),
sampler=eval_sampler,
batch_size=args.batch_size,
pin_memory=True)
lr_scheduler = CosineAnnealingLR(optim, train_dataloader.__len__() // 100)
strategy_dict = strategy.prepare(dict(model=model, optimizer=optim, lr_scheduler=lr_scheduler))
model = strategy_dict['model']
optim = strategy_dict['optimizer']
lr_scheduler = strategy_dict['lr_scheduler']
trainer = RewardModelTrainer(model=model,
strategy=strategy,
optim=optim,
lr_scheduler=lr_scheduler,
loss_fn=loss_fn,
max_epochs=args.max_epochs)
trainer.fit(train_dataloader=train_dataloader, valid_dataloader=valid_dataloader, eval_dataloader=eval_dataloader)
# save model checkpoint after fitting on only rank0
strategy.save_model(model, args.save_path, only_rank0=True)
# save optimizer checkpoint on all ranks
if args.need_optim_ckpt:
strategy.save_optimizer(trainer.optimizer,
'rm_optim_checkpoint_%d.pt' % (torch.cuda.current_device()),
only_rank0=False)
if __name__ == '__main__':
parser = argparse.ArgumentParser()
parser.add_argument('--strategy',
choices=['ddp', 'colossalai_gemini', 'colossalai_zero2'],
default='colossalai_zero2')
parser.add_argument('--model', choices=['gpt2', 'bloom', 'opt', 'llama'], default='bloom')
parser.add_argument('--pretrain', type=str, default=None)
parser.add_argument('--model_path', type=str, default=None)
parser.add_argument('--need_optim_ckpt', type=bool, default=False)
parser.add_argument('--dataset',
type=str,
choices=['Anthropic/hh-rlhf', 'Dahoas/rm-static'],
default='Dahoas/rm-static')
parser.add_argument('--subset', type=str, default=None)
parser.add_argument('--save_path', type=str, default='rm_ckpt')
parser.add_argument('--max_epochs', type=int, default=1)
parser.add_argument('--batch_size', type=int, default=1)
parser.add_argument('--max_len', type=int, default=512)
parser.add_argument('--lora_rank', type=int, default=0, help="low-rank adaptation matrices rank")
parser.add_argument('--loss_fn', type=str, default='log_sig', choices=['log_sig', 'log_exp'])
parser.add_argument('--test', type=bool, default=False)
args = parser.parse_args()
train(args)