fix swag example for work with apex

This commit is contained in:
thomwolf 2018-12-13 13:35:59 +01:00
parent 0cf88ff084
commit 0f544625f4
3 changed files with 59 additions and 78 deletions

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@ -442,12 +442,12 @@ python run_swag.py \
--do_train \
--do_lower_case \
--do_eval \
--data_dir $SWAG_DIR/data
--data_dir $SWAG_DIR/data \
--train_batch_size 16 \
--learning_rate 2e-5 \
--num_train_epochs 3.0 \
--max_seq_length 80 \
--output_dir /tmp/swag_output/
--output_dir /tmp/swag_output/ \
--gradient_accumulation_steps 4
```

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@ -1,5 +1,6 @@
# coding=utf-8
# Copyright 2018 The Google AI Language Team Authors and The HugginFace Inc. team.
# Copyright (c) 2018, NVIDIA CORPORATION. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
@ -232,34 +233,10 @@ def select_field(features, field):
for feature in features
]
def copy_optimizer_params_to_model(named_params_model, named_params_optimizer):
""" Utility function for optimize_on_cpu and 16-bits training.
Copy the parameters optimized on CPU/RAM back to the model on GPU
"""
for (name_opti, param_opti), (name_model, param_model) in zip(named_params_optimizer, named_params_model):
if name_opti != name_model:
logger.error("name_opti != name_model: {} {}".format(name_opti, name_model))
raise ValueError
param_model.data.copy_(param_opti.data)
def set_optimizer_params_grad(named_params_optimizer, named_params_model, test_nan=False):
""" Utility function for optimize_on_cpu and 16-bits training.
Copy the gradient of the GPU parameters to the CPU/RAMM copy of the model
"""
is_nan = False
for (name_opti, param_opti), (name_model, param_model) in zip(named_params_optimizer, named_params_model):
if name_opti != name_model:
logger.error("name_opti != name_model: {} {}".format(name_opti, name_model))
raise ValueError
if param_model.grad is not None:
if test_nan and torch.isnan(param_model.grad).sum() > 0:
is_nan = True
if param_opti.grad is None:
param_opti.grad = torch.nn.Parameter(param_opti.data.new().resize_(*param_opti.data.size()))
param_opti.grad.data.copy_(param_model.grad.data)
else:
param_opti.grad = None
return is_nan
def warmup_linear(x, warmup=0.002):
if x < warmup:
return x/warmup
return 1.0 - x
def main():
parser = argparse.ArgumentParser()
@ -335,17 +312,15 @@ def main():
type=int,
default=1,
help="Number of updates steps to accumulate before performing a backward/update pass.")
parser.add_argument('--optimize_on_cpu',
default=False,
action='store_true',
help="Whether to perform optimization and keep the optimizer averages on CPU")
parser.add_argument('--fp16',
default=False,
action='store_true',
help="Whether to use 16-bit float precision instead of 32-bit")
parser.add_argument('--loss_scale',
type=float, default=128,
help='Loss scaling, positive power of 2 values can improve fp16 convergence.')
type=float, default=0,
help="Loss scaling to improve fp16 numeric stability. Only used when fp16 set to True.\n"
"0 (default value): dynamic loss scaling.\n"
"Positive power of 2: static loss scaling value.\n")
args = parser.parse_args()
@ -353,13 +328,11 @@ def main():
device = torch.device("cuda" if torch.cuda.is_available() and not args.no_cuda else "cpu")
n_gpu = torch.cuda.device_count()
else:
torch.cuda.set_device(args.local_rank)
device = torch.device("cuda", args.local_rank)
n_gpu = 1
# Initializes the distributed backend which will take care of sychronizing nodes/GPUs
torch.distributed.init_process_group(backend='nccl')
if args.fp16:
logger.info("16-bits training currently not supported in distributed training")
args.fp16 = False # (see https://github.com/pytorch/pytorch/pull/13496)
logger.info("device %s n_gpu %d distributed training %r", device, n_gpu, bool(args.local_rank != -1))
if args.gradient_accumulation_steps < 1:
@ -399,32 +372,50 @@ def main():
model.half()
model.to(device)
if args.local_rank != -1:
model = torch.nn.parallel.DistributedDataParallel(model, device_ids=[args.local_rank],
output_device=args.local_rank)
try:
from apex.parallel import DistributedDataParallel as DDP
except ImportError:
raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use distributed and fp16 training.")
model = DDP(model)
elif n_gpu > 1:
model = torch.nn.DataParallel(model)
# Prepare optimizer
if args.fp16:
param_optimizer = [(n, param.clone().detach().to('cpu').float().requires_grad_()) \
for n, param in model.named_parameters()]
elif args.optimize_on_cpu:
param_optimizer = [(n, param.clone().detach().to('cpu').requires_grad_()) \
for n, param in model.named_parameters()]
else:
param_optimizer = list(model.named_parameters())
no_decay = ['bias', 'gamma', 'beta']
param_optimizer = list(model.named_parameters())
# hack to remove pooler, which is not used
# thus it produce None grad that break apex
param_optimizer = [n for n in param_optimizer if 'pooler' not in n[0]]
no_decay = ['bias', 'LayerNorm.bias', 'LayerNorm.weight']
optimizer_grouped_parameters = [
{'params': [p for n, p in param_optimizer if not any(nd in n for nd in no_decay)], 'weight_decay_rate': 0.01},
{'params': [p for n, p in param_optimizer if any(nd in n for nd in no_decay)], 'weight_decay_rate': 0.0}
{'params': [p for n, p in param_optimizer if not any(nd in n for nd in no_decay)], 'weight_decay': 0.01},
{'params': [p for n, p in param_optimizer if any(nd in n for nd in no_decay)], 'weight_decay': 0.0}
]
t_total = num_train_steps
if args.local_rank != -1:
t_total = t_total // torch.distributed.get_world_size()
optimizer = BertAdam(optimizer_grouped_parameters,
lr=args.learning_rate,
warmup=args.warmup_proportion,
t_total=t_total)
if args.fp16:
try:
from apex.optimizers import FP16_Optimizer
from apex.optimizers import FusedAdam
except ImportError:
raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use distributed and fp16 training.")
optimizer = FusedAdam(optimizer_grouped_parameters,
lr=args.learning_rate,
bias_correction=False,
max_grad_norm=1.0)
if args.loss_scale == 0:
optimizer = FP16_Optimizer(optimizer, dynamic_loss_scale=True)
else:
optimizer = FP16_Optimizer(optimizer, static_loss_scale=args.loss_scale)
else:
optimizer = BertAdam(optimizer_grouped_parameters,
lr=args.learning_rate,
warmup=args.warmup_proportion,
t_total=t_total)
global_step = 0
if args.do_train:
@ -461,28 +452,18 @@ def main():
loss = loss * args.loss_scale
if args.gradient_accumulation_steps > 1:
loss = loss / args.gradient_accumulation_steps
loss.backward()
tr_loss += loss.item()
nb_tr_examples += input_ids.size(0)
nb_tr_steps += 1
if args.fp16:
optimizer.backward(loss)
else:
loss.backward()
if (step + 1) % args.gradient_accumulation_steps == 0:
if args.fp16 or args.optimize_on_cpu:
if args.fp16 and args.loss_scale != 1.0:
# scale down gradients for fp16 training
for param in model.parameters():
if param.grad is not None:
param.grad.data = param.grad.data / args.loss_scale
is_nan = set_optimizer_params_grad(param_optimizer, model.named_parameters(), test_nan=True)
if is_nan:
logger.info("FP16 TRAINING: Nan in gradients, reducing loss scaling")
args.loss_scale = args.loss_scale / 2
model.zero_grad()
continue
optimizer.step()
copy_optimizer_params_to_model(model.named_parameters(), param_optimizer)
else:
optimizer.step()
model.zero_grad()
# modify learning rate with special warm up BERT uses
lr_this_step = args.learning_rate * warmup_linear(global_step/t_total, args.warmup_proportion)
for param_group in optimizer.param_groups:
param_group['lr'] = lr_this_step
optimizer.step()
optimizer.zero_grad()
global_step += 1
if args.do_eval and (args.local_rank == -1 or torch.distributed.get_rank() == 0):

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@ -35,7 +35,7 @@ class OptimizationTest(unittest.TestCase):
criterion = torch.nn.MSELoss()
# No warmup, constant schedule, no gradient clipping
optimizer = BertAdam(params=[w], lr=2e-1,
weight_decay_rate=0.0,
weight_decay=0.0,
max_grad_norm=-1)
for _ in range(100):
loss = criterion(w, target)