ColossalAI/applications/Chat/coati/trainer/rm.py

136 lines
5.9 KiB
Python

from abc import ABC
from datetime import datetime
from typing import Optional
import pandas as pd
import torch
import torch.distributed as dist
from torch.optim import Optimizer, lr_scheduler
from torch.utils.data import DataLoader, Dataset, DistributedSampler
from tqdm import tqdm
from transformers.tokenization_utils_base import PreTrainedTokenizerBase
from .strategies import Strategy
from .utils import is_rank_0
class RewardModelTrainer(ABC):
"""
Trainer to use while training reward model.
Args:
model (torch.nn.Module): the model to train
strategy (Strategy): the strategy to use for training
optim(Optimizer): the optimizer to use for training
loss_fn (callable): the loss function to use for training
train_dataset (Dataset): the dataset to use for training
valid_dataset (Dataset): the dataset to use for validation
eval_dataset (Dataset): the dataset to use for evaluation
batch_size (int, defaults to 1): the batch size while training
max_epochs (int, defaults to 2): the number of epochs to train
"""
def __init__(
self,
model,
strategy: Strategy,
optim: Optimizer,
loss_fn,
train_dataset: Dataset,
valid_dataset: Dataset,
eval_dataset: Dataset,
batch_size: int = 1,
max_epochs: int = 1,
) -> None:
super().__init__()
self.strategy = strategy
self.epochs = max_epochs
train_sampler = None
if dist.is_initialized() and dist.get_world_size() > 1:
train_sampler = DistributedSampler(train_dataset, shuffle=True, seed=42, drop_last=True)
self.train_dataloader = DataLoader(train_dataset,
shuffle=(train_sampler is None),
sampler=train_sampler,
batch_size=batch_size)
self.valid_dataloader = DataLoader(valid_dataset, batch_size=batch_size, shuffle=True)
self.eval_dataloader = DataLoader(eval_dataset, batch_size=batch_size, shuffle=True)
self.model = strategy.setup_model(model)
self.loss_fn = loss_fn
self.optimizer = strategy.setup_optimizer(optim, self.model)
self.scheduler = lr_scheduler.CosineAnnealingLR(self.optimizer, self.train_dataloader.__len__() // 100)
def eval_acc(self, dataloader):
dist = 0
on = 0
cnt = 0
self.model.eval()
with torch.no_grad():
for chosen_ids, c_mask, reject_ids, r_mask in dataloader:
chosen_ids = chosen_ids.squeeze(1).to(torch.cuda.current_device())
c_mask = c_mask.squeeze(1).to(torch.cuda.current_device())
reject_ids = reject_ids.squeeze(1).to(torch.cuda.current_device())
r_mask = r_mask.squeeze(1).to(torch.cuda.current_device())
chosen_reward = self.model(chosen_ids, attention_mask=c_mask)
reject_reward = self.model(reject_ids, attention_mask=r_mask)
for i in range(len(chosen_reward)):
cnt += 1
if chosen_reward[i] > reject_reward[i]:
on += 1
dist += (chosen_reward - reject_reward).mean().item()
dist_mean = dist / len(dataloader)
acc = on / cnt
self.model.train()
return dist_mean, acc
def fit(self):
time = datetime.now()
epoch_bar = tqdm(range(self.epochs), desc='Train epoch', disable=not is_rank_0())
for epoch in range(self.epochs):
step_bar = tqdm(range(self.train_dataloader.__len__()),
desc='Train step of epoch %d' % epoch,
disable=not is_rank_0())
# train
self.model.train()
cnt = 0
acc = 0
dist = 0
for chosen_ids, c_mask, reject_ids, r_mask in self.train_dataloader:
chosen_ids = chosen_ids.squeeze(1).to(torch.cuda.current_device())
c_mask = c_mask.squeeze(1).to(torch.cuda.current_device())
reject_ids = reject_ids.squeeze(1).to(torch.cuda.current_device())
r_mask = r_mask.squeeze(1).to(torch.cuda.current_device())
chosen_reward = self.model(chosen_ids, attention_mask=c_mask)
reject_reward = self.model(reject_ids, attention_mask=r_mask)
loss = self.loss_fn(chosen_reward, reject_reward)
self.strategy.backward(loss, self.model, self.optimizer)
self.strategy.optimizer_step(self.optimizer)
self.optimizer.zero_grad()
cnt += 1
if cnt == 100:
self.scheduler.step()
dist, acc = self.eval_acc(self.valid_dataloader)
cnt = 0
if is_rank_0():
log = pd.DataFrame([[step_bar.n, loss.item(), dist, acc]],
columns=['step', 'loss', 'dist', 'acc'])
log.to_csv('log_%s.csv' % time, mode='a', header=False, index=False)
step_bar.update()
step_bar.set_postfix({'dist': dist, 'acc': acc})
# eval
dist, acc = self.eval_acc(self.eval_dataloader)
if is_rank_0():
log = pd.DataFrame([[step_bar.n, loss.item(), dist, acc]], columns=['step', 'loss', 'dist', 'acc'])
log.to_csv('log.csv', mode='a', header=False, index=False)
epoch_bar.update()
step_bar.set_postfix({'dist': dist, 'acc': acc})
step_bar.close()
def save_model(self,
path: str,
only_rank0: bool = False,
tokenizer: Optional[PreTrainedTokenizerBase] = None) -> None:
self.strategy.save_model(model=self.model, path=path, only_rank0=only_rank0, tokenizer=tokenizer)