def optimize(self, trainer: 'CallbackTrainer'):
trainer.batch_grad_norm = training_util.rescale_gradients(trainer.model, self.grad_norm)
trainer.optimizer.step()
# Update the description with the latest metrics
trainer.train_metrics.update(
training_util.get_metrics(trainer.model, trainer.train_loss, trainer.batches_this_epoch)
)
def train_on_batch(self, batch, optimizer):
"""
written by ph to keep interface between models consistent
"""
# to cuda
batch['tokens']['tokens'] = batch['tokens']['tokens'].cuda()
batch['verb_indicator'] = batch['verb_indicator'].cuda()
batch['tags'] = batch['tags'].cuda()
# forward + loss
optimizer.zero_grad()
output_dict = self(**batch) # input is dict[str, tensor]
loss = output_dict["loss"] + self.get_regularization_penalty()
if torch.isnan(loss):
raise ValueError("nan loss encountered")
# backward + update
loss.backward()
rescale_gradients(self, self.max_grad_norm)
optimizer.step()
return loss
def rescale_gradients(self) -> Optional[float]:
return training_util.rescale_gradients(self.model, self._grad_norm)
def rescale_gradients(self, trainer: 'CallbackTrainer'):
trainer.batch_grad_norm = training_util.rescale_gradients(trainer.model, self.grad_norm)
def _rescale_gradients(self) -> Optional[float]:
"""
Performs gradient rescaling. Is a no-op if gradient rescaling is not enabled.
"""
return training_util.rescale_gradients(self._model, self._grad_norm)
def _train_epoch(self, epoch: int) -> Dict[str, float]:
"""
Trains one epoch and returns metrics.
"""
logger.info("Epoch %d/%d", epoch, self._num_epochs)
peak_cpu_usage = peak_memory_mb()
logger.info(f"Peak CPU memory usage MB: {peak_cpu_usage}")
gpu_usage = []
for gpu, memory in gpu_memory_mb().items():
gpu_usage.append((gpu, memory))
logger.info(f"GPU {gpu} memory usage MB: {memory}")
train_loss = 0.0
# Set the model to "train" mode.
self._pytorch_model.train()
num_training_batches = [math.ceil(
self.iterator.get_num_batches(train_data) / self._num_gradient_accumulation_steps
) for task, train_data in self.train_datas.items()]
assert len(set(num_training_batches)) == 1, "num_training_batches doesn't agree"
tasks = list(self.batch_group_generators.keys())
num_tasks = len(tasks)
#if isinstance(self._learning_rate_scheduler, SlantedTriangular):
# old_num_steps_per_epoch = self._learning_rate_scheduler.num_steps_per_epoch
# self._learning_rate_scheduler.num_steps_per_epoch = num_training_batches[0]
# logger.info(f"modify num_steps_per_epoch of lr scheduler from"
# f"{old_num_steps_per_epoch} to {num_training_batches}")
self._last_log = time.time()
last_save_time = time.time()
batches_this_epoch = 0
if self._batch_num_total is None:
self._batch_num_total = 0
logger.info("Training")
cumulative_batch_group_size = 0
tqdm_bar = Tqdm.tqdm(range(num_training_batches[0]))
for _ in tqdm_bar:
randperms = torch.randperm(len(tasks)).tolist()
sampled_tasks = [tasks[idx] for idx in randperms[:self._tasks_per_step]]
sampled_task_generators = [next(self.batch_group_generators[task]) for task in sampled_tasks]
batches_this_epoch += 1
self._batch_num_total += 1
batch_num_total = self._batch_num_total
self.optimizer.zero_grad()
task_metrics = self.wrapper(tasks=sampled_task_generators, train=True, meta_train=True)
losses = [list(map(lambda x: x["loss"], metrics)) for metrics in task_metrics]
LASes = [list(map(lambda x: x["metric"]["LAS"], metrics)) for metrics in task_metrics]
names = ["loss", "LAS"]
list_values = [losses, LASes]
if self.has_VIB:
KLDivs = [list(map(lambda x: x["metric"]["kl_div"], metrics)) for metrics in task_metrics]
names.append("KLDiv")
list_values.append(KLDivs)
if self.has_pos:
pos_accs = [list(map(lambda x: x["metric"].get("pos_accuracy", 0.0), metrics)) for metrics in task_metrics]
names.append("pos_acc")
list_values.append(pos_accs)
for name, values in zip(names, list_values):
self._writer.log({f"step_{name}_{task}_{i}": value
for task, task_values in zip(sampled_tasks, values)
for i, value in enumerate(task_values)},
step=self._batch_num_total)
values_inner_steps = list(map(np.mean, zip(*values)))
self._writer.log({f"step_{name}_{i}": value for i, value in
enumerate(values_inner_steps)},
step=self._batch_num_total)
if name == "loss":
train_loss += values_inner_steps[0]
batch_grad_norm = self.rescale_gradients()
# This does nothing if batch_num_total is None or you are using a
# scheduler which doesn't update per batch.
if self._learning_rate_scheduler:
self._learning_rate_scheduler.step_batch(batch_num_total)
if self._momentum_scheduler:
self._momentum_scheduler.step_batch(batch_num_total)
# variational information bottleneck / meta-learning without memorization
if self.has_VIB:
kl_loss, kl_div, kl_div2 = ContinuousVIB.get_kl_loss(self.model, sampled_task_generators)
kl_loss.backward()
self._writer.log({"kl_loss": kl_loss.detach().item(),
"kl_div": kl_div,
"kl_div2": kl_div2},
step=self._batch_num_total)
# adversarial training
if self.task_D and self.optim_D:
# D training
self.optimizer.step()
steps_per_update = self.task_D.steps_per_update
if (batch_num_total - 1) % steps_per_update == 0:
self.optim_D.zero_grad()
hidden_states, labels, masks = self.task_D.get_hidden_states(
self.model,
sampled_task_generators
)
D_loss, _, acc = self.task_D(hidden_states, labels, masks, detach=True)
D_loss.backward()
disc_grad_norm = training_util.rescale_gradients(self.task_D, self.task_D.disc_grad_norm)
self.optim_D.step()
self._writer.log({"D_loss": D_loss.detach().item(),
"D_acc": acc},
step=self._batch_num_total)
if disc_grad_norm:
self._writer.log({"D_grad_norm": disc_grad_norm.detach().item()},
step=self._batch_num_total)
# G training
hidden_states, labels, masks = self.task_D.get_hidden_states(
self.model,
sampled_task_generators
)
_, g_loss, acc = self.task_D(hidden_states, labels, masks)
if self.task_D.weight:
alpha = self.task_D.weight
else:
alpha = self.task_D.get_alpha(self._batch_num_total,
num_training_batches[0] * self._num_epochs)
G_loss = -alpha * g_loss
G_loss.backward()
gen_grad_norm = training_util.rescale_gradients(self.model, self.task_D.gen_grad_norm)
self._writer.log({"G_loss": g_loss.detach().item(), "alpha": alpha, "G_acc": acc},
step=self._batch_num_total)
if gen_grad_norm:
self._writer.log({"G_grad_norm": gen_grad_norm.detach().item()},
step=self._batch_num_total)
self.optimizer.step()
# Update moving averages
if self._moving_average is not None:
self._moving_average.apply(batch_num_total)
# Update the description with the latest metrics
metrics = training_util.get_metrics(
self.wrapper.container,
train_loss,
batches_this_epoch,
world_size=self._world_size,
cuda_device=[self.cuda_device],
)
# Updating tqdm only for the master as the trainers wouldn't have one
if self._master:
description = training_util.description_from_metrics(metrics)
tqdm_bar.set_description(description, refresh=False)
# log learning rate.
self._writer.log({"lr": self.optimizer.param_groups[0]['lr']},
step=self._batch_num_total)
# Save model if needed.
if (
self._model_save_interval is not None
and (time.time() - last_save_time > self._model_save_interval)
and self._master
):
last_save_time = time.time()
self._save_checkpoint(
"{0}.{1}".format(epoch, training_util.time_to_str(int(last_save_time)))
)
# Let all workers finish their epoch before computing
# the final statistics for the epoch.
if self._distributed:
dist.barrier()
metrics = training_util.get_metrics(
self.wrapper.container,
train_loss,
batches_this_epoch,
reset=True,
world_size=self._world_size,
cuda_device=[self.cuda_device],
)
metrics["cpu_memory_MB"] = peak_cpu_usage
for (gpu_num, memory) in gpu_usage:
metrics["gpu_" + str(gpu_num) + "_memory_MB"] = memory
return metrics
