def val(model, criterion, dataloader, epoch=None, val_writer=None, lr=None, msglogger=None):
with t.no_grad():
"""
计算模型在验证集上的准确率等信息
"""
model.eval()
val_losses = AverageMeter()
val_top1 = AverageMeter()
val_top5 = AverageMeter()
val_progressor = None
if not msglogger:
val_progressor = ProgressBar(mode="Val ", epoch=epoch, total_epoch=opt.max_epoch, model_name=opt.model,
lr=lr,
total=len(dataloader))
for ii, (data, labels, img_path,tag) in enumerate(dataloader):
if not check_date(img_path, tag, msglogger): return
input = data.to(opt.device)
labels = labels.to(opt.device)
score = model(input)
loss = criterion(score, labels)
precision1, precision5 = accuracy(score, labels, topk=(1, 5)) # top1 和 top5 的准确率
val_losses.update(loss.item(), input.size(0))
val_top1.update(precision1[0].item(), input.size(0))
val_top5.update(precision5[0].item(), input.size(0))
if val_progressor:
val_progressor.current = ii + 1
val_progressor.current_loss = val_losses.avg
val_progressor.current_top1 = val_top1.avg
val_progressor.current_top5 = val_top5.avg
val_progressor()
if ii % opt.print_freq == 0:
if val_writer:
grid = make_grid((input.data.cpu() * 0.225 + 0.45).clamp(min=0, max=1))
val_writer.add_image('val_images', grid, ii * (epoch + 1)) # 测试图片
val_writer.add_scalar('loss', val_losses.avg, ii * (epoch + 1)) # 训练误差
val_writer.add_text('top1', 'val accuracy top1 %.2f%%' % val_top1.avg,
ii * (epoch + 1)) # top1准确率文本
val_writer.add_scalars('accuracy', {'top1': val_top1.avg,
'top5': val_top5.avg,
'loss': val_losses.avg}, ii * (epoch + 1))
if msglogger:
msglogger.info('==> Top1: %.3f Top5: %.3f Loss: %.3f\n',
val_top1.avg, val_top5.avg, val_losses.avg)
return [val_losses.avg, val_top1.avg, val_top5.avg]
def train(**kwargs):
opt._parse(kwargs)
train_writer = None
value_writer = None
if opt.vis:
train_writer = SummaryWriter(
log_dir='./runs/train_' +
datetime.now().strftime('%y%m%d-%H-%M-%S'))
value_writer = SummaryWriter(
log_dir='./runs/val_' + datetime.now().strftime('%y%m%d-%H-%M-%S'))
previous_loss = 1e10 # 上次学习的loss
best_precision = 0 # 最好的精确度
start_epoch = 0
lr = opt.lr
perf_scores_history = [] # 绩效分数
# step1: criterion and optimizer
# 1. 铰链损失（Hinge Loss）：主要用于支持向量机（SVM） 中；
# 2. 互熵损失 （Cross Entropy Loss，Softmax Loss ）：用于Logistic 回归与Softmax 分类中；
# 3. 平方损失（Square Loss）：主要是最小二乘法（OLS）中；
# 4. 指数损失（Exponential Loss） ：主要用于Adaboost 集成学习算法中；
# 5. 其他损失（如0-1损失，绝对值损失）
criterion = t.nn.CrossEntropyLoss().to(opt.device) # 损失函数
# step2: meters
train_losses = AverageMeter() # 误差仪表
train_top1 = AverageMeter() # top1 仪表
train_top5 = AverageMeter() # top5 仪表
pylogger = PythonLogger(msglogger)
# step3: configure model
model = getattr(models, opt.model)() # 获得网络结构
compression_scheduler = distiller.CompressionScheduler(model)
optimizer = model.get_optimizer(lr, opt.weight_decay) # 优化器
if opt.load_model_path:
# # 把所有的张量加载到CPU中
# t.load(opt.load_model_path, map_location=lambda storage, loc: storage)
# t.load(opt.load_model_path, map_location='cpu')
# # 把所有的张量加载到GPU 1中
# t.load(opt.load_model_path, map_location=lambda storage, loc: storage.cuda(1))
# # 把张量从GPU 1 移动到 GPU 0
# t.load(opt.load_model_path, map_location={'cuda:1': 'cuda:0'})
checkpoint = t.load(opt.load_model_path)
start_epoch = checkpoint["epoch"]
# compression_scheduler.load_state_dict(checkpoint['compression_scheduler'], False)
best_precision = checkpoint["best_precision"]
model.load_state_dict(checkpoint["state_dict"])
optimizer = checkpoint['optimizer']
model.to(opt.device) # 加载模型到 GPU
if opt.compress:
compression_scheduler = distiller.file_config(
model, optimizer, opt.compress, compression_scheduler) # 加载模型修剪计划表
model.to(opt.device)
# 学习速率调整器
lr_scheduler = get_scheduler(optimizer, opt)
# step4: data_image
train_data = DatasetFromFilename(opt.data_root, flag='train') # 训练集
val_data = DatasetFromFilename(opt.data_root, flag='test') # 验证集
train_dataloader = DataLoader(train_data,
opt.batch_size,
shuffle=True,
num_workers=opt.num_workers) # 训练集加载器
val_dataloader = DataLoader(val_data,
opt.batch_size,
shuffle=True,
num_workers=opt.num_workers) # 验证集加载器
# train
for epoch in range(start_epoch, opt.max_epoch):
model.train()
if opt.pruning:
compression_scheduler.on_epoch_begin(epoch) # epoch 开始修剪
train_losses.reset() # 重置仪表
train_top1.reset() # 重置仪表
# print('训练数据集大小', len(train_dataloader))
total_samples = len(train_dataloader.sampler)
steps_per_epoch = math.ceil(total_samples / opt.batch_size)
train_progressor = ProgressBar(mode="Train ",
epoch=epoch,
total_epoch=opt.max_epoch,
model_name=opt.model,
lr=lr,
total=len(train_dataloader))
lr = lr_scheduler.get_lr()[0]
for ii, (data, labels, img_path, tag) in enumerate(train_dataloader):
if not check_date(img_path, tag, msglogger): return
if opt.pruning:
compression_scheduler.on_minibatch_begin(
epoch, ii, steps_per_epoch, optimizer) # batch 开始修剪
train_progressor.current = ii + 1 # 训练集当前进度
# train model
input = data.to(opt.device)
target = labels.to(opt.device)
if train_writer:
grid = make_grid(
(input.data.cpu() * 0.225 + 0.45).clamp(min=0, max=1))
train_writer.add_image('train_images', grid,
ii * (epoch + 1)) # 训练图片
score = model(input) # 网络结构返回值
# 计算损失
loss = criterion(score, target)
if opt.pruning:
# Before running the backward phase, we allow the scheduler to modify the loss
# (e.g. add regularization loss)
agg_loss = compression_scheduler.before_backward_pass(
epoch,
ii,
steps_per_epoch,
loss,
optimizer=optimizer,
return_loss_components=True) # 模型修建误差
loss = agg_loss.overall_loss
train_losses.update(loss.item(), input.size(0))
# loss = criterion(score[0], target) # 计算损失 Inception3网络
optimizer.zero_grad() # 参数梯度设成0
loss.backward() # 反向传播
optimizer.step() # 更新参数
if opt.pruning:
compression_scheduler.on_minibatch_end(epoch, ii,
steps_per_epoch,
optimizer) # batch 结束修剪
precision1_train, precision5_train = accuracy(
score, target, topk=(1, 5)) # top1 和 top5 的准确率
# writer.add_graph(model, input)
# precision1_train, precision2_train = accuracy(score[0], target, topk=(1, 2)) # Inception3网络
train_losses.update(loss.item(), input.size(0))
train_top1.update(precision1_train[0].item(), input.size(0))
train_top5.update(precision5_train[0].item(), input.size(0))
train_progressor.current_loss = train_losses.avg
train_progressor.current_top1 = train_top1.avg
train_progressor.current_top5 = train_top5.avg
train_progressor() # 打印进度
if ii % opt.print_freq == 0:
if train_writer:
train_writer.add_scalar('loss', train_losses.avg,
ii * (epoch + 1)) # 训练误差
train_writer.add_text(
'top1', 'train accuracy top1 %s' % train_top1.avg,
ii * (epoch + 1)) # top1准确率文本
train_writer.add_scalars(
'accuracy', {
'top1': train_top1.avg,
'top5': train_top5.avg,
'loss': train_losses.avg
}, ii * (epoch + 1))
# train_progressor.done() # 保存训练结果为txt
# validate and visualize
if opt.pruning:
distiller.log_weights_sparsity(model, epoch,
loggers=[pylogger]) # 打印模型修剪结果
compression_scheduler.on_epoch_end(epoch, optimizer) # epoch 结束修剪
val_loss, val_top1, val_top5 = val(model, criterion, val_dataloader,
epoch, value_writer, lr) # 校验模型
sparsity = distiller.model_sparsity(model)
perf_scores_history.append(
distiller.MutableNamedTuple(
{
'sparsity': sparsity,
'top1': val_top1,
'top5': val_top5,
'epoch': epoch + 1,
'lr': lr,
'loss': val_loss
}, ))
# 保持绩效分数历史记录从最好到最差的排序
# 按稀疏度排序为主排序键，然后按top1、top5、epoch排序
perf_scores_history.sort(key=operator.attrgetter(
'sparsity', 'top1', 'top5', 'epoch'),
reverse=True)
for score in perf_scores_history[:1]:
msglogger.info(
'==> Best [Top1: %.3f Top5: %.3f Sparsity: %.2f on epoch: %d Lr: %f Loss: %f]',
score.top1, score.top5, score.sparsity, score.epoch, lr,
score.loss)
best_precision = max(perf_scores_history[0].top1,
best_precision) # 最大top1 准确率
is_best = epoch + 1 == perf_scores_history[
0].epoch # 当前epoch 和最佳epoch 一样
if is_best:
model.save({
"epoch":
epoch + 1,
"model_name":
opt.model,
"state_dict":
model.state_dict(),
"best_precision":
best_precision,
"optimizer":
optimizer,
"valid_loss": [val_loss, val_top1, val_top5],
'compression_scheduler':
compression_scheduler.state_dict(),
}) # 保存模型
# update learning rate
lr_scheduler.step(epoch) # 更新学习效率
# 如果训练误差比上次大 降低学习效率
# if train_losses.val > previous_loss:
# lr = lr * opt.lr_decay
# # 当loss大于上一次loss,降低学习率
# for param_group in optimizer.param_groups:
# param_group['lr'] = lr
#
# previous_loss = train_losses.val
t.cuda.empty_cache() # 这个命令是清除没用的临时变量的
def train(self):
previous_loss = 1e10 # 上次学习的loss
lr = self.opt.lr
perf_scores_history = []
pylogger = PythonLogger(msglogger)
self.train_load_model()
self.load_compress()
self.create_write()
lr_scheduler = get_scheduler(self.optimizer, opt)
for epoch in range(self.start_epoch, self.opt.max_epoch):
self.model.train()
self.load_data()
if self.opt.pruning:
self.compression_scheduler.on_epoch_begin(epoch) # epoch 开始修剪
self.train_losses.reset() # 重置仪表
self.train_top1.reset() # 重置仪表
# print('训练数据集大小', len(train_dataloader))
total_samples = len(self.train_dataloader.sampler)
steps_per_epoch = math.ceil(total_samples / self.opt.batch_size)
train_progressor = ProgressBar(mode="Train ",
epoch=epoch,
total_epoch=self.opt.max_epoch,
model_name=self.opt.model,
total=len(self.train_dataloader))
lr = lr_scheduler.get_lr()
for ii, (data, labels,
img_path) in enumerate(self.train_dataloader):
if self.opt.pruning:
self.compression_scheduler.on_minibatch_begin(
epoch, ii, steps_per_epoch,
self.optimizer) # batch 开始修剪
train_progressor.current = ii + 1 # 训练集当前进度
# train model
input = data.to(self.opt.device)
target = labels.to(self.opt.device)
score = self.model(input) # 网络结构返回值
loss = self.criterion(score, target) # 计算损失
if self.opt.pruning:
# Before running the backward phase, we allow the scheduler to modify the loss
# (e.g. add regularization loss)
agg_loss = self.compression_scheduler.before_backward_pass(
epoch,
ii,
steps_per_epoch,
loss,
optimizer=self.optimizer,
return_loss_components=True) # 模型修建误差
loss = agg_loss.overall_loss
self.train_losses.update(loss.item(), input.size(0))
# loss = criterion(score[0], target) # 计算损失 Inception3网络
self.optimizer.zero_grad() # 参数梯度设成0
loss.backward() # 反向传播
self.optimizer.step() # 更新参数
if opt.pruning:
self.compression_scheduler.on_minibatch_end(
epoch, ii, steps_per_epoch,
self.optimizer) # batch 结束修剪
precision1_train, precision5_train = accuracy(
score, target, topk=(1, 5)) # top1 和 top5 的准确率
# precision1_train, precision2_train = accuracy(score[0], target, topk=(1, 2)) # Inception3网络
self.train_losses.update(loss.item(), input.size(0))
self.train_top1.update(precision1_train[0].item(),
input.size(0))
self.train_top5.update(precision5_train[0].item(),
input.size(0))
train_progressor.current_loss = self.train_losses.avg
train_progressor.current_top1 = self.train_top1.avg
train_progressor.current_top5 = self.train_top5.avg
train_progressor() # 打印进度
if (ii + 1) % self.opt.print_freq == 0:
self.visualization_train(input, ii, epoch)
if self.opt.pruning:
distiller.log_weights_sparsity(self.model,
epoch,
loggers=[pylogger]) # 打印模型修剪结果
self.compression_scheduler.on_epoch_end(
epoch, self.optimizer) # epoch 结束修剪
val_loss, val_top1, val_top5 = val(self.model, self.criterion,
self.val_dataloader, epoch,
self.value_writer) # 校验模型
sparsity = distiller.model_sparsity(self.model)
perf_scores_history.append(
distiller.MutableNamedTuple(
{
'sparsity': sparsity,
'top1': val_top1,
'top5': val_top5,
'epoch': epoch + 1,
'lr': lr,
'loss': val_loss
}, ))
# 保持绩效分数历史记录从最好到最差的排序
# 按稀疏度排序为主排序键，然后按top1、top5、epoch排序
perf_scores_history.sort(key=operator.attrgetter(
'sparsity', 'top1', 'top5', 'epoch'),
reverse=True)
for score in perf_scores_history[:1]:
msglogger.info(
'==> Best [Top1: %.3f Top5: %.3f Sparsity: %.2f on epoch: %d Lr: %f Loss: %f]',
score.top1, score.top5, score.sparsity, score.epoch, lr,
score.loss)
is_best = epoch == perf_scores_history[
0].epoch # 当前epoch 和最佳epoch 一样
self.best_precision = max(perf_scores_history[0].top1,
self.best_precision) # 最大top1 准确率
if is_best:
self.train_save_model(epoch, val_loss, val_top1, val_top5)
# update learning rate
lr = lr_scheduler.get_lr()
# # 如果训练误差比上次大 降低学习效率
# if self.train_losses.val > previous_loss:
# lr = lr * self.opt.lr_decay
# # 当loss大于上一次loss,降低学习率
# for param_group in self.optimizer.param_groups:
# param_group['lr'] = lr
#
# previous_loss = self.train_losses.val
t.cuda.empty_cache()
