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

106 lines
4.3 KiB
Python

from datetime import datetime
from typing import Callable
import pandas as pd
import torch
import tqdm
from torch.optim import Optimizer
from torch.optim.lr_scheduler import _LRScheduler
from torch.utils.data import DataLoader
from .base import SLTrainer
from .strategies import Strategy
from .utils import is_rank_0
class RewardModelTrainer(SLTrainer):
"""
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
lr_scheduler (_LRScheduler): the lr scheduler to use for training
loss_fn (callable): the loss function to use for training
max_epochs (int, defaults to 2): the number of epochs to train
"""
def __init__(
self,
model,
strategy: Strategy,
optim: Optimizer,
lr_scheduler: _LRScheduler,
loss_fn: Callable,
max_epochs: int = 1,
) -> None:
super().__init__(strategy, max_epochs, model, optim)
self.loss_fn = loss_fn
self.scheduler = lr_scheduler
def _eval(self, epoch):
if self.eval_dataloader is not None:
self.model.eval()
dist, on, cnt = 0, 0, 0
with torch.no_grad():
for chosen_ids, c_mask, reject_ids, r_mask in self.eval_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()
self.dist = dist / len(self.eval_dataloader)
self.acc = on / cnt
if is_rank_0():
log = pd.DataFrame(
[[(epoch + 1) * len(self.train_dataloader), self.loss.item(), self.dist, self.acc]],
columns=["step", "loss", "dist", "acc"],
)
log.to_csv("log.csv", mode="a", header=False, index=False)
def _train(self, epoch):
self.model.train()
step_bar = tqdm.trange(
len(self.train_dataloader), desc="Train step of epoch %d" % epoch, disable=not is_rank_0()
)
cnt = 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)
self.loss = self.loss_fn(chosen_reward, reject_reward)
self.strategy.backward(self.loss, self.model, self.optimizer)
self.strategy.optimizer_step(self.optimizer)
self.optimizer.zero_grad()
cnt += 1
if cnt % 100 == 0:
self.scheduler.step()
step_bar.update()
step_bar.close()
def _before_fit(self, train_dataloader: DataLoader, valid_dataloader: DataLoader, eval_dataloader: DataLoader):
"""
Args:
train_dataloader (DataLoader): the dataloader to use for training
valid_dataloader (DataLoader): the dataloader to use for validation
eval_dataloader (DataLoader): the dataloader to use for evaluation
"""
super()._before_fit()
self.datetime = datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
self.train_dataloader = train_dataloader
self.valid_dataloader = valid_dataloader
self.eval_dataloader = eval_dataloader