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from __future__ import print_function
import sys
import argparse
import os
import shutil
import time
import random
import numpy as np
import math
import torch
import torch.nn as nn
import torch.nn.parallel
import torch.nn.functional as F
import torch.backends.cudnn as cudnn
import torch.distributed as dist
import torch.optim as optim
import torch.utils.data as data
import torch.utils.data.distributed
import torchvision.transforms as transforms
import torchvision.datasets as datasets
import torchvision.models as models
import models.imagenet as customized_models
from flops_counter import get_model_complexity_info
from PIL import ImageFile
ImageFile.LOAD_TRUNCATED_IMAGES = True
from utils import Bar, Logger, AverageMeter, accuracy, mkdir_p
import warnings
warnings.filterwarnings('ignore')
try:
from apex.parallel import DistributedDataParallel as DDP
from apex.fp16_utils import *
from apex import amp, optimizers
except ImportError:
raise ImportError("Please install apex from https://www.github.com/nvidia/apex to run this example.")
# for servers to immediately record the logs
def flush_print(func):
def new_print(*args, **kwargs):
func(*args, **kwargs)
sys.stdout.flush()
return new_print
print = flush_print(print)
# Models
default_model_names = sorted(name for name in models.__dict__
if name.islower() and not name.startswith("__")
and callable(models.__dict__[name]))
customized_models_names = sorted(name for name in customized_models.__dict__
if name.islower() and not name.startswith("__")
and callable(customized_models.__dict__[name]))
for name in customized_models.__dict__:
if name.islower() and not name.startswith("__") and callable(customized_models.__dict__[name]):
models.__dict__[name] = customized_models.__dict__[name]
model_names = default_model_names + customized_models_names
# Parse arguments
parser = argparse.ArgumentParser(description='PyTorch ImageNet Training')
# Datasets
parser.add_argument('-d', '--data', default='path to dataset', type=str)
parser.add_argument('-j', '--workers', default=32, type=int, metavar='N',
help='number of data loading workers (default: 4)')
# Optimization options
parser.add_argument('--opt-level', default='O2', type=str,
help='O2 is mixed FP16/32 training, see more in https://github.com/NVIDIA/apex/tree/f5cd5ae937f168c763985f627bbf850648ea5f3f/examples/imagenet')
parser.add_argument('--keep-batchnorm-fp32', default=True, action='store_true',
help='keeping cudnn bn leads to fast training')
parser.add_argument('--loss-scale', type=float, default=None)
parser.add_argument('--mixup', dest='mixup', action='store_true',
help='whether to use mixup')
parser.add_argument('--alpha', default=0.2, type=float,
metavar='mixup alpha', help='alpha value for mixup B(alpha, alpha) distribution')
parser.add_argument('--cos', dest='cos', action='store_true',
help='using cosine decay lr schedule')
parser.add_argument('--warmup', '--wp', default=5, type=int,
help='number of epochs to warmup')
parser.add_argument('--epochs', default=120, type=int, metavar='N',
help='number of total epochs to run')
parser.add_argument('--start-epoch', default=0, type=int, metavar='N',
help='manual epoch number (useful on restarts)')
parser.add_argument('--train-batch', default=256, type=int, metavar='N',
help='train batchsize (default: 256)')
parser.add_argument('--test-batch', default=125, type=int, metavar='N',
help='test batchsize (default: 200)')
parser.add_argument('--lr', '--learning-rate', default=0.1, type=float,
metavar='LR', help='initial learning rate')
parser.add_argument('--drop', '--dropout', default=0, type=float,
metavar='Dropout', help='Dropout ratio')
parser.add_argument('--schedule', type=int, nargs='+', default=[30, 60, 90],
help='Decrease learning rate at these epochs.')
parser.add_argument('--gamma', type=float, default=0.1, help='LR is multiplied by gamma on schedule.')
parser.add_argument('--momentum', default=0.9, type=float, metavar='M',
help='momentum')
parser.add_argument('--weight-decay', '--wd', default=1e-4, type=float,
metavar='W', help='weight decay (default: 1e-4)')
parser.add_argument('--wd-all', dest = 'wdall', action='store_true',
help='weight decay on all parameters')
# Checkpoints
parser.add_argument('--print-freq', '-p', default=10, type=int,
metavar='N', help='print frequency (default: 10)')
parser.add_argument('-c', '--checkpoint', default='checkpoint', type=str, metavar='PATH',
help='path to save checkpoint (default: checkpoint)')
parser.add_argument('--resume', default='', type=str, metavar='PATH',
help='path to latest checkpoint (default: none)')
# Architecture
parser.add_argument('--arch', '-a', metavar='ARCH', default='resnet18',
choices=model_names,
help='model architecture: ' +
' | '.join(model_names) +
' (default: resnet18)')
parser.add_argument('--depth', type=int, default=29, help='Model depth.')
parser.add_argument('--cardinality', type=int, default=32, help='ResNet cardinality (group).')
parser.add_argument('--base-width', type=int, default=4, help='ResNet base width.')
parser.add_argument('--widen-factor', type=int, default=4, help='Widen factor. 4 -> 64, 8 -> 128, ...')
# Miscs
parser.add_argument('--manualSeed', type=int, help='manual seed')
parser.add_argument('-e', '--evaluate', dest='evaluate', action='store_true',
help='evaluate model on validation set')
parser.add_argument('--pretrained', dest='pretrained', action='store_true',
help='use pre-trained model')
#Device options
#parser.add_argument('--gpu-id', default='0', type=str, help='id(s) for CUDA_VISIBLE_DEVICES')
parser.add_argument('--local_rank', default=0, type=int)
args = parser.parse_args()
state = {k: v for k, v in args._get_kwargs()}
print("opt_level = {}".format(args.opt_level))
print("keep_batchnorm_fp32 = {}".format(args.keep_batchnorm_fp32), type(args.keep_batchnorm_fp32))
print("loss_scale = {}".format(args.loss_scale), type(args.loss_scale))
# Use CUDA
# os.environ['CUDA_VISIBLE_DEVICES'] = args.gpu_id
use_cuda = torch.cuda.is_available()
# Random seed
if args.manualSeed is None:
args.manualSeed = random.randint(1, 10000)
random.seed(args.manualSeed)
torch.manual_seed(args.manualSeed)
if use_cuda:
torch.cuda.manual_seed_all(args.manualSeed)
best_acc = 0 # best test accuracy
def fast_collate(batch):
imgs = [img[0] for img in batch]
targets = torch.tensor([target[1] for target in batch], dtype=torch.int64)
w = imgs[0].size[0]
h = imgs[0].size[1]
tensor = torch.zeros((len(imgs), 3, h, w), dtype=torch.uint8)
for i, img in enumerate(imgs):
nump_array = np.asarray(img, dtype=np.uint8)
# tens = torch.from_numpy(nump_array)
if nump_array.ndim < 3:
nump_array = np.expand_dims(nump_array, axis=-1)
nump_array = np.rollaxis(nump_array, 2)
tensor[i] += torch.from_numpy(nump_array)
return tensor, targets
class data_prefetcher():
def __init__(self, loader):
self.loader = iter(loader)
self.stream = torch.cuda.Stream()
self.mean = torch.tensor([0.485 * 255, 0.456 * 255, 0.406 * 255]) \
.cuda().view(1, 3, 1, 1)
self.std = torch.tensor([0.229 * 255, 0.224 * 255, 0.225 * 255]) \
.cuda().view(1, 3, 1, 1)
self.preload()
def preload(self):
try:
self.next_input, self.next_target = next(self.loader)
except StopIteration:
self.next_input = None
self.next_target = None
return
with torch.cuda.stream(self.stream):
self.next_input = self.next_input.cuda(non_blocking=True)
self.next_target = self.next_target.cuda(non_blocking=True)
self.next_input = self.next_input.float()
self.next_input = self.next_input.sub_(self.mean).div_(self.std)
def next(self):
torch.cuda.current_stream().wait_stream(self.stream)
input = self.next_input
target = self.next_target
if input is not None:
self.preload()
return input, target
def main():
global best_acc
start_epoch = args.start_epoch # start from epoch 0 or last checkpoint epoch
if not os.path.isdir(args.checkpoint) and args.local_rank == 0:
mkdir_p(args.checkpoint)
args.distributed = True
args.gpu = args.local_rank
torch.cuda.set_device(args.gpu)
torch.distributed.init_process_group(backend='nccl', init_method='env://')
args.world_size = torch.distributed.get_world_size()
print('world_size = ', args.world_size)
assert torch.backends.cudnn.enabled, "Amp requires cudnn backend to be enabled."
# create model
if args.pretrained:
print("=> using pre-trained model '{}'".format(args.arch))
model = models.__dict__[args.arch](pretrained=True)
elif 'resnext' in args.arch:
model = models.__dict__[args.arch](
baseWidth=args.base_width,
cardinality=args.cardinality,
)
else:
print("=> creating model '{}'".format(args.arch))
model = models.__dict__[args.arch]()
flops, params = get_model_complexity_info(model, (224, 224), as_strings=False, print_per_layer_stat=False)
print('Flops: %.3f' % (flops / 1e9))
print('Params: %.2fM' % (params / 1e6))
cudnn.benchmark = True
# define loss function (criterion) and optimizer
# criterion = nn.CrossEntropyLoss().cuda()
criterion = SoftCrossEntropyLoss(label_smoothing=0.1).cuda()
model = model.cuda()
args.lr = float(args.lr * float(args.train_batch*args.world_size)/256.) # default args.lr = 0.1 -> 256
optimizer = set_optimizer(model)
#optim.SGD(model.parameters(), lr=args.lr, momentum=args.momentum, weight_decay=args.weight_decay)
model, optimizer = amp.initialize(model, optimizer,
opt_level=args.opt_level,
keep_batchnorm_fp32=args.keep_batchnorm_fp32,
loss_scale=args.loss_scale)
#model = torch.nn.DataParallel(model).cuda()
#model = torch.nn.parallel.DistributedDataParallel(model, device_ids=[args.local_rank], output_device=args.local_rank)
model = DDP(model, delay_allreduce=True)
# Data loading code
traindir = os.path.join(args.data, 'train')
valdir = os.path.join(args.data, 'valf')
#normalize = transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
data_aug_scale = (0.08, 1.0)
train_dataset = datasets.ImageFolder(traindir, transforms.Compose([
transforms.RandomResizedCrop(224, scale = data_aug_scale),
transforms.RandomHorizontalFlip(),
# transforms.ToTensor(),
# normalize,
]))
val_dataset = datasets.ImageFolder(valdir, transforms.Compose([
transforms.Resize(256),
transforms.CenterCrop(224),
# transforms.ToTensor(),
# normalize,
]))
train_sampler = torch.utils.data.distributed.DistributedSampler(train_dataset)
val_sampler = torch.utils.data.distributed.DistributedSampler(val_dataset)
train_loader = torch.utils.data.DataLoader(
train_dataset, batch_size=args.train_batch, shuffle=False,
num_workers=args.workers, pin_memory=True, sampler=train_sampler, collate_fn=fast_collate)
val_loader = torch.utils.data.DataLoader(
val_dataset, batch_size=args.test_batch, shuffle=False,
num_workers=args.workers, pin_memory=True, sampler=val_sampler, collate_fn=fast_collate)
# Resume
title = 'ImageNet-' + args.arch
if args.resume:
# Load checkpoint.
print('==> Resuming from checkpoint..', args.resume)
assert os.path.isfile(args.resume), 'Error: no checkpoint directory found!'
args.checkpoint = os.path.dirname(args.resume)
checkpoint = torch.load(args.resume)
best_acc = checkpoint['best_acc']
start_epoch = checkpoint['epoch']
# model may have more keys
t = model.state_dict()
c = checkpoint['state_dict']
flag = True
for k in t:
if k not in c:
print('not in loading dict! fill it', k, t[k])
c[k] = t[k]
flag = False
model.load_state_dict(c)
#if flag:
# print('optimizer load old state')
# optimizer.load_state_dict(checkpoint['optimizer'])
#else:
print('new optimizer !')
if args.local_rank == 0:
logger = Logger(os.path.join(args.checkpoint, 'log.txt'), title=title, resume=True)
else:
if args.local_rank == 0:
logger = Logger(os.path.join(args.checkpoint, 'log.txt'), title=title)
logger.set_names(['Learning Rate', 'Train Loss', 'Valid Loss', 'Train Acc.', 'Valid Acc.'])
if args.evaluate:
print('\nEvaluation only')
test_loss, test_acc = test(val_loader, model, criterion, start_epoch, use_cuda)
print(' Test Loss: %.8f, Test Acc: %.2f' % (test_loss, test_acc))
return
scheduler = CosineAnnealingLR(optimizer,
args.epochs, len(train_loader), eta_min=0., warmup=args.warmup)
# Train and val
for epoch in range(start_epoch, args.epochs):
train_sampler.set_epoch(epoch)
if args.local_rank == 0:
print('\nEpoch: [%d | %d]' % (epoch + 1, args.epochs))
train_loss, train_acc = train(train_loader, model, criterion, optimizer, epoch, scheduler, use_cuda)
test_loss, test_acc = test(val_loader, model, criterion, epoch, use_cuda)
# save model
if args.local_rank == 0:
# append logger file
logger.append([state['lr'], train_loss, test_loss, train_acc, test_acc])
is_best = test_acc > best_acc
best_acc = max(test_acc, best_acc)
save_checkpoint({
'epoch': epoch + 1,
'state_dict': model.state_dict(),
'acc': test_acc,
'best_acc': best_acc,
'optimizer' : optimizer.state_dict(),
}, is_best, checkpoint=args.checkpoint)
if args.local_rank == 0:
logger.close()
print('Best acc:')
print(best_acc)
def train(train_loader, model, criterion, optimizer, epoch, scheduler, use_cuda):
# switch to train mode
model.train()
torch.set_grad_enabled(True)
batch_time = AverageMeter()
losses = AverageMeter()
top1 = AverageMeter()
top5 = AverageMeter()
end = time.time()
if args.local_rank == 0:
bar = Bar('Processing', max=len(train_loader))
show_step = len(train_loader) // 10
prefetcher = data_prefetcher(train_loader)
inputs, targets = prefetcher.next()
batch_idx = -1
while inputs is not None:
batch_idx += 1
lr = scheduler.update(epoch, batch_idx)
batch_size = inputs.size(0)
if batch_size < args.train_batch:
break
if args.mixup:
inputs, targets_a, targets_b, lam = mixup_data(inputs, targets, args.alpha, use_cuda)
outputs = model(inputs)
loss_func = mixup_criterion(targets_a, targets_b, lam)
old_loss = loss_func(criterion, outputs)
else:
outputs = model(inputs)
old_loss = criterion(outputs, targets)
# compute gradient and do SGD step
optimizer.zero_grad()
# loss.backward()
with amp.scale_loss(old_loss, optimizer) as loss:
loss.backward()
optimizer.step()
if batch_idx % args.print_freq == 0:
# measure accuracy and record loss
prec1, prec5 = accuracy(outputs.data, targets.data, topk=(1, 5))
reduced_loss = reduce_tensor(loss.data)
prec1 = reduce_tensor(prec1)
prec5 = reduce_tensor(prec5)
# to_python_float incurs a host<->device sync
losses.update(to_python_float(reduced_loss), inputs.size(0))
top1.update(to_python_float(prec1), inputs.size(0))
top5.update(to_python_float(prec5), inputs.size(0))
torch.cuda.synchronize()
# measure elapsed time
batch_time.update((time.time() - end) / args.print_freq)
end = time.time()
if args.local_rank == 0: # plot progress
bar.suffix = '({batch}/{size}) lr({lr:.6f}) | Batch: {bt:.3f}s | Total: {total:} | Loss: {loss:.4f} | top1: {top1: .4f} | top5: {top5: .4f}'.format(
lr=lr[0],
batch=batch_idx + 1,
size=len(train_loader),
bt=batch_time.val,
total=bar.elapsed_td,
loss=losses.avg,
top1=top1.avg,
top5=top5.avg,
)
bar.next()
if (batch_idx) % show_step == 0 and args.local_rank == 0:
print('E%d' % (epoch) + bar.suffix)
inputs, targets = prefetcher.next()
if args.local_rank == 0:
bar.finish()
return (losses.avg, top1.avg)
def test(val_loader, model, criterion, epoch, use_cuda):
global best_acc
batch_time = AverageMeter()
losses = AverageMeter()
top1 = AverageMeter()
top5 = AverageMeter()
# switch to evaluate mode
model.eval()
# torch.set_grad_enabled(False)
end = time.time()
if args.local_rank == 0:
bar = Bar('Processing', max=len(val_loader))
prefetcher = data_prefetcher(val_loader)
inputs, targets = prefetcher.next()
batch_idx = -1
while inputs is not None:
batch_idx += 1
# compute output
with torch.no_grad():
outputs = model(inputs)
loss = criterion(outputs, targets)
# measure accuracy and record loss
prec1, prec5 = accuracy(outputs.data, targets.data, topk=(1, 5))
reduced_loss = reduce_tensor(loss.data)
prec1 = reduce_tensor(prec1)
prec5 = reduce_tensor(prec5)
# to_python_float incurs a host<->device sync
losses.update(to_python_float(reduced_loss), inputs.size(0))
top1.update(to_python_float(prec1), inputs.size(0))
top5.update(to_python_float(prec5), inputs.size(0))
# measure elapsed time
batch_time.update(time.time() - end)
end = time.time()
# plot progress
if args.local_rank == 0:
bar.suffix = 'Valid({batch}/{size}) | Batch: {bt:.3f}s | Total: {total:} | Loss: {loss:.4f} | top1: {top1: .4f} | top5: {top5: .4f}'.format(
batch=batch_idx + 1,
size=len(val_loader),
bt=batch_time.avg,
total=bar.elapsed_td,
loss=losses.avg,
top1=top1.avg,
top5=top5.avg,
)
bar.next()
inputs, targets = prefetcher.next()
if args.local_rank == 0:
print(bar.suffix)
bar.finish()
return (losses.avg, top1.avg)
def save_checkpoint(state, is_best, checkpoint='checkpoint', filename='checkpoint.pth.tar'):
filepath = os.path.join(checkpoint, filename)
torch.save(state, filepath)
if is_best:
shutil.copyfile(filepath, os.path.join(checkpoint, 'model_best.pth.tar'))
def set_optimizer(model):
if args.wdall:
optimizer = optim.SGD(model.parameters(), lr=args.lr, momentum=args.momentum, weight_decay=args.weight_decay)
print('weight decay on all parameters')
else:
no_decay_list = []
decay_list = []
no_decay_name = []
decay_name = []
for m in model.modules():
if (hasattr(m, 'groups') and m.groups > 1) or isinstance(m, nn.BatchNorm2d) \
or m.__class__.__name__ == 'GL':
no_decay_list += m.parameters(recurse=False)
for name, p in m.named_parameters(recurse=False):
no_decay_name.append(m.__class__.__name__ + name)
#print('listlen = ', len(no_decay_list), 'namelen = ', len(no_decay_name))
else:
for name, p in m.named_parameters(recurse=False):
if 'bias' in name:
no_decay_list.append(p)
no_decay_name.append(m.__class__.__name__ + name)
else:
decay_list.append(p)
decay_name.append(m.__class__.__name__ + name)
print('no decay list = ', no_decay_name)
print('decay list = ', decay_name)
params = [{'params': no_decay_list, 'weight_decay': 0} \
, {'params': decay_list}]
optimizer = optim.SGD(params, lr=args.lr, momentum=args.momentum, weight_decay=args.weight_decay)
print('optimizer = ', optimizer)
return optimizer
class SoftCrossEntropyLoss(nn.NLLLoss):
def __init__(self, label_smoothing=0, num_classes=1000, **kwargs):
assert label_smoothing >= 0 and label_smoothing <= 1
super(SoftCrossEntropyLoss, self).__init__(**kwargs)
self.confidence = 1 - label_smoothing
self.other = label_smoothing * 1.0 / (num_classes - 1)
self.criterion = nn.KLDivLoss(reduction='batchmean')
print('using soft celoss!!!, label_smoothing = ', label_smoothing)
def forward(self, input, target):
one_hot = torch.zeros_like(input)
one_hot.fill_(self.other)
one_hot.scatter_(1, target.unsqueeze(1).long(), self.confidence)
input = F.log_softmax(input, 1)
return self.criterion(input, one_hot)
def mixup_data(x, y, alpha=1.0, use_cuda=True):
if alpha > 0.:
lam = np.random.beta(alpha, alpha)
else:
lam = 1.
batch_size = x.size(0)
if use_cuda:
index = torch.randperm(batch_size).cuda()
else:
index = torch.randperm(batch_size)
mixed_x = lam * x + (1 - lam) * x[index, ...]
y_a, y_b = y, y[index]
return mixed_x, y_a, y_b, lam
def mixup_criterion(y_a, y_b, lam):
return lambda criterion, pred: lam * criterion(pred, y_a) + (1 - lam) * criterion(pred, y_b)
def reduce_tensor(tensor):
rt = tensor.clone()
dist.all_reduce(rt, op=dist.ReduceOp.SUM)
rt /= args.world_size
return rt
class CosineAnnealingLR(object):
def __init__(self, optimizer, T_max, N_batch, eta_min=0, last_epoch=-1, warmup=0):
if not isinstance(optimizer, torch.optim.Optimizer):
raise TypeError('{} is not an Optimizer'.format(
type(optimizer).__name__))
self.optimizer = optimizer
self.T_max = T_max
self.N_batch = N_batch
self.eta_min = eta_min
self.warmup = warmup
if last_epoch == -1:
for group in optimizer.param_groups:
group.setdefault('initial_lr', group['lr'])
else:
for i, group in enumerate(optimizer.param_groups):
if 'initial_lr' not in group:
raise KeyError("param 'initial_lr' is not specified "
"in param_groups[{}] when resuming an optimizer".format(i))
self.base_lrs = list(map(lambda group: group['initial_lr'], optimizer.param_groups))
self.update(last_epoch+1)
self.last_epoch = last_epoch
self.iter = 0
def state_dict(self):
return {key: value for key, value in self.__dict__.items() if key != 'optimizer'}
def load_state_dict(self, state_dict):
self.__dict__.update(state_dict)
def get_lr(self):
if self.last_epoch < self.warmup:
lrs = [base_lr * (self.last_epoch + self.iter / self.N_batch) / self.warmup for base_lr in self.base_lrs]
else:
lrs = [self.eta_min + (base_lr - self.eta_min) *
(1 + math.cos(math.pi * (self.last_epoch - self.warmup + self.iter / self.N_batch) / (self.T_max - self.warmup))) / 2
for base_lr in self.base_lrs]
return lrs
def update(self, epoch, batch=0):
self.last_epoch = epoch
self.iter = batch + 1
lrs = self.get_lr()
for param_group, lr in zip(self.optimizer.param_groups, lrs):
param_group['lr'] = lr
return lrs
if __name__ == '__main__':
main()