AstrAI/khaosz/trainer/trainer.py

99 lines
3.7 KiB
Python

import logging
from typing import Optional, List
from khaosz.config import TrainConfig
from khaosz.trainer.train_callback import (
TrainCallback,
ProgressBarCallback,
CheckpointCallback,
GradientClippingCallback,
SchedulerCallback
)
from khaosz.trainer.train_context import TrainContext, TrainContextBuilder
from khaosz.trainer.checkpoint import Checkpoint
from khaosz.parallel.setup import spawn_parallel_fn
logger = logging.getLogger(__name__)
class Trainer:
def __init__(
self,
train_config: TrainConfig,
callbacks: Optional[List[TrainCallback]] = None
):
self.train_config = train_config
self.callbacks = callbacks or self._get_default_callbacks()
def _get_default_callbacks(self) -> List[TrainCallback]:
train_config = self.train_config
return [
ProgressBarCallback(train_config.n_epoch),
CheckpointCallback(train_config.checkpoint_dir, train_config.checkpoint_interval),
GradientClippingCallback(train_config.max_grad_norm),
SchedulerCallback(),
]
def _build_context(self, checkpoint: Optional[Checkpoint]) -> TrainContext:
return (TrainContextBuilder(self.train_config)
.with_checkpoint(checkpoint)
.with_dataloader()
.with_strategy()
.build())
def _call_callbacks(self, method_name: str, context: TrainContext):
for callback in self.callbacks:
method = getattr(callback, method_name, None)
if method:
method(context)
def train(self, checkpoint: Optional[Checkpoint] = None):
config = self.train_config
spawn_parallel_fn(
self._train_impl,
backend=config.backend,
world_size=config.nprocs,
master_addr=config.master_addr,
master_port=config.master_port,
checkpoint=checkpoint
)
def _train_impl(self, checkpoint: Optional[Checkpoint] = None) -> Checkpoint:
context = self._build_context(checkpoint)
self._call_callbacks('on_train_begin', context)
try:
context.model.train()
# 1.epoch
for epoch in range(context.epoch, self.train_config.n_epoch):
context.epoch = epoch
self._call_callbacks('on_epoch_begin', context)
for batch in context.dataloader:
if context.iteration % self.train_config.accumulation_steps == 0:
# 2. step
self._call_callbacks('on_step_begin', context)
context.optimizer.step()
context.optimizer.zero_grad()
self._call_callbacks('on_step_end', context)
# 3. batch
self._call_callbacks('on_batch_begin', context)
loss = context.strategy(batch)
context.loss = loss.item()
context.iteration += 1
# to make the loss normalized by accumulation steps
stand_batch = self.train_config.accumulation_steps * self.train_config.nprocs
stand_loss = loss / stand_batch
stand_loss.backward()
self._call_callbacks('on_batch_end', context)
self._call_callbacks('on_epoch_end', context)
except Exception as e:
logger.error(f"Training failed: {str(e)}", exc_info=True)
self._call_callbacks('on_error', context)
raise
finally:
self._call_callbacks('on_train_end', context)