Add some Nvidia performance enhancements (prefetch loader, fast collate), and refactor some of training and model fact/transforms

data/__init__.py

@@ -0,0 +1,4 @@
+from data.dataset import Dataset
+from data.transforms import transforms_imagenet_eval, transforms_imagenet_train
+from data.utils import fast_collate, PrefetchLoader
+from data.random_erasing import RandomErasingTorch, RandomErasingNumpy

data/random_erasing.py

@@ -0,0 +1,131 @@
+from __future__ import absolute_import
+
+#from torchvision.transforms import *
+
+from PIL import Image
+import random
+import math
+import numpy as np
+import torch
+
+
+class RandomErasingNumpy:
+    """ Randomly selects a rectangle region in an image and erases its pixels.
+        'Random Erasing Data Augmentation' by Zhong et al.
+        See https://arxiv.org/pdf/1708.04896.pdf
+
+        This 'Numpy' variant of RandomErasing is intended to be applied on a per
+        image basis after transforming the image to uint8 numpy array in
+        range 0-255 prior to tensor conversion and normalization
+    Args:
+         probability: The probability that the Random Erasing operation will be performed.
+         sl: Minimum proportion of erased area against input image.
+         sh: Maximum proportion of erased area against input image.
+         r1: Minimum aspect ratio of erased area.
+         mean: Erasing value.
+    """
+
+    def __init__(
+            self,
+            probability=0.5, sl=0.02, sh=1/3, min_aspect=0.3,
+            per_pixel=False, rand_color=False,
+            pl=0, ph=255, mean=[255 * 0.485, 255 * 0.456, 255 * 0.406],
+            out_type=np.uint8):
+        self.probability = probability
+        if not per_pixel and not rand_color:
+            self.mean = np.array(mean).round().astype(out_type)
+        else:
+            self.mean = None
+        self.sl = sl
+        self.sh = sh
+        self.min_aspect = min_aspect
+        self.pl = pl
+        self.ph = ph
+        self.per_pixel = per_pixel  # per pixel random, bounded by [pl, ph]
+        self.rand_color = rand_color  # per block random, bounded by [pl, ph]
+        self.out_type = out_type
+
+    def __call__(self, img):
+        if random.random() > self.probability:
+            return img
+
+        chan, img_h, img_w = img.shape
+        area = img_h * img_w
+        for attempt in range(100):
+            target_area = random.uniform(self.sl, self.sh) * area
+            aspect_ratio = random.uniform(self.min_aspect, 1 / self.min_aspect)
+
+            h = int(round(math.sqrt(target_area * aspect_ratio)))
+            w = int(round(math.sqrt(target_area / aspect_ratio)))
+            if self.rand_color:
+                c = np.random.randint(self.pl, self.ph + 1, (chan,), self.out_type)
+            elif not self.per_pixel:
+                c = self.mean[:chan]
+            if w < img_w and h < img_h:
+                top = random.randint(0, img_h - h)
+                left = random.randint(0, img_w - w)
+                if self.per_pixel:
+                    img[:, top:top + h, left:left + w] = np.random.randint(
+                        self.pl, self.ph + 1, (chan, h, w), self.out_type)
+                else:
+                    img[:, top:top + h, left:left + w] = c
+                return img
+
+        return img
+
+
+class RandomErasingTorch:
+    """ Randomly selects a rectangle region in an image and erases its pixels.
+        'Random Erasing Data Augmentation' by Zhong et al.
+        See https://arxiv.org/pdf/1708.04896.pdf
+
+        This 'Torch' variant of RandomErasing is intended to be applied to a full batch
+        tensor after it has been normalized by dataset mean and std.
+    Args:
+         probability: The probability that the Random Erasing operation will be performed.
+         sl: Minimum proportion of erased area against input image.
+         sh: Maximum proportion of erased area against input image.
+         r1: Minimum aspect ratio of erased area.
+    """
+
+    def __init__(
+            self,
+            probability=0.5, sl=0.02, sh=1/3, min_aspect=0.3,
+            per_pixel=False, rand_color=False,
+            device='cuda'):
+        self.probability = probability
+        self.sl = sl
+        self.sh = sh
+        self.min_aspect = min_aspect
+        self.per_pixel = per_pixel  # per pixel random, bounded by [pl, ph]
+        self.rand_color = rand_color  # per block random, bounded by [pl, ph]
+        self.device = device
+
+    def __call__(self, batch):
+        batch_size, chan, img_h, img_w = batch.size()
+        area = img_h * img_w
+        for i in range(batch_size):
+            if random.random() > self.probability:
+                continue
+            img = batch[i]
+            for attempt in range(100):
+                target_area = random.uniform(self.sl, self.sh) * area
+                aspect_ratio = random.uniform(self.min_aspect, 1 / self.min_aspect)
+
+                h = int(round(math.sqrt(target_area * aspect_ratio)))
+                w = int(round(math.sqrt(target_area / aspect_ratio)))
+                if self.rand_color:
+                    c = torch.empty(chan, dtype=batch.dtype, device=self.device).normal_()
+                elif not self.per_pixel:
+                    c = torch.zeros(chan, dtype=batch.dtype, device=self.device)
+                if w < img_w and h < img_h:
+                    top = random.randint(0, img_h - h)
+                    left = random.randint(0, img_w - w)
+                    if self.per_pixel:
+                        img[:, top:top + h, left:left + w] = torch.empty(
+                            (chan, h, w), dtype=batch.dtype, device=self.device).normal_()
+                    else:
+                        img[:, top:top + h, left:left + w] = c
+                    break
+
+        return batch

data/transforms.py

@@ -0,0 +1,53 @@
+import torch
+from torchvision import transforms
+from PIL import Image
+import math
+import numpy as np
+from data.random_erasing import RandomErasingNumpy
+
+DEFAULT_CROP_PCT = 0.875
+
+IMAGENET_DPN_MEAN = [124 / 255, 117 / 255, 104 / 255]
+IMAGENET_DPN_STD = [1 / (.0167 * 255)] * 3
+IMAGENET_INCEPTION_MEAN = [0.5, 0.5, 0.5]
+IMAGENET_INCEPTION_STD = [0.5, 0.5, 0.5]
+IMAGENET_DEFAULT_MEAN = [0.485, 0.456, 0.406]
+IMAGENET_DEFAULT_STD = [0.229, 0.224, 0.225]
+
+
+class AsNumpy:
+
+    def __call__(self, pil_img):
+        np_img = np.array(pil_img, dtype=np.uint8)
+        if np_img.ndim < 3:
+            np_img = np.expand_dims(np_img, axis=-1)
+        np_img = np.rollaxis(np_img, 2)  # HWC to CHW
+        return np_img
+
+
+def transforms_imagenet_train(
+        img_size=224,
+        scale=(0.1, 1.0),
+        color_jitter=(0.4, 0.4, 0.4),
+        random_erasing=0.4):
+
+    tfl = [
+        transforms.RandomResizedCrop(img_size, scale=scale),
+        transforms.RandomHorizontalFlip(),
+        transforms.ColorJitter(*color_jitter),
+        AsNumpy(),
+    ]
+    #if random_erasing > 0.:
+    #    tfl.append(RandomErasingNumpy(random_erasing, per_pixel=True))
+    return transforms.Compose(tfl)
+
+
+def transforms_imagenet_eval(img_size=224, crop_pct=None):
+    crop_pct = crop_pct or DEFAULT_CROP_PCT
+    scale_size = int(math.floor(img_size / crop_pct))
+
+    return transforms.Compose([
+        transforms.Resize(scale_size, Image.BICUBIC),
+        transforms.CenterCrop(img_size),
+        AsNumpy(),
+    ])

data/utils.py

@@ -0,0 +1,65 @@
+import torch
+from data.random_erasing import RandomErasingTorch
+
+
+def fast_collate(batch):
+    targets = torch.tensor([b[1] for b in batch], dtype=torch.int64)
+    batch_size = len(targets)
+    tensor = torch.zeros((batch_size, *batch[0][0].shape), dtype=torch.uint8)
+    for i in range(batch_size):
+        tensor[i] += torch.from_numpy(batch[i][0])
+
+    return tensor, targets
+
+
+class PrefetchLoader:
+
+    def __init__(self,
+            loader,
+            fp16=False,
+            random_erasing=True,
+            mean=[0.485, 0.456, 0.406],
+            std=[0.229, 0.224, 0.225]):
+        self.loader = loader
+        self.fp16 = fp16
+        self.random_erasing = random_erasing
+        self.mean = torch.tensor([x * 255 for x in mean]).cuda().view(1, 3, 1, 1)
+        self.std = torch.tensor([x * 255 for x in std]).cuda().view(1, 3, 1, 1)
+        if random_erasing:
+            self.random_erasing = RandomErasingTorch(per_pixel=True)
+        else:
+            self.random_erasing = None
+
+        if self.fp16:
+            self.mean = self.mean.half()
+            self.std = self.std.half()
+
+    def __iter__(self):
+        stream = torch.cuda.Stream()
+        first = True
+
+        for next_input, next_target in self.loader:
+            with torch.cuda.stream(stream):
+                next_input = next_input.cuda(non_blocking=True)
+                next_target = next_target.cuda(non_blocking=True)
+                if self.fp16:
+                    next_input = next_input.half()
+                else:
+                    next_input = next_input.float()
+                next_input = next_input.sub_(self.mean).div_(self.std)
+                if self.random_erasing is not None:
+                    next_input = self.random_erasing(next_input)
+
+            if not first:
+                yield input, target
+            else:
+                first = False
+
+            torch.cuda.current_stream().wait_stream(stream)
+            input = next_input
+            target = next_target
+
+        yield input, target
+
+    def __len__(self):
+        return len(self.loader)

models/__init__.py

@@ -1,2 +1,2 @@
 from .model_factory import create_model
-from .transforms import transforms_imagenet_eval, transforms_imagenet_train
+

models/model_factory.py

@@ -1,7 +1,4 @@
 import torch
-from torchvision import transforms
-from PIL import Image
-import math
 import os
 
 from .inception_v4 import inception_v4

models/random_erasing.py

@@ -1,61 +0,0 @@
-from __future__ import absolute_import
-
-from torchvision.transforms import *
-
-from PIL import Image
-import random
-import math
-import numpy as np
-import torch
-
-
-class RandomErasing:
-    """ Randomly selects a rectangle region in an image and erases its pixels.
-        'Random Erasing Data Augmentation' by Zhong et al.
-        See https://arxiv.org/pdf/1708.04896.pdf
-    Args:
-         probability: The probability that the Random Erasing operation will be performed.
-         sl: Minimum proportion of erased area against input image.
-         sh: Maximum proportion of erased area against input image.
-         r1: Minimum aspect ratio of erased area.
-         mean: Erasing value.
-    """
-
-    def __init__(
-            self,
-            probability=0.5, sl=0.02, sh=1/3, min_aspect=0.3,
-            per_pixel=False, random=False,
-            pl=0, ph=1., mean=[0.485, 0.456, 0.406]):
-        self.probability = probability
-        self.mean = torch.tensor(mean)
-        self.sl = sl
-        self.sh = sh
-        self.min_aspect = min_aspect
-        self.pl = pl
-        self.ph = ph
-        self.per_pixel = per_pixel  # per pixel random, bounded by [pl, ph]
-        self.random = random  # per block random, bounded by [pl, ph]
-
-    def __call__(self, img):
-        if random.random() > self.probability:
-            return img
-
-        chan, img_h, img_w = img.size()
-        area = img_h * img_w
-        for attempt in range(100):
-            target_area = random.uniform(self.sl, self.sh) * area
-            aspect_ratio = random.uniform(self.min_aspect, 1 / self.min_aspect)
-
-            h = int(round(math.sqrt(target_area * aspect_ratio)))
-            w = int(round(math.sqrt(target_area / aspect_ratio)))
-            c = torch.empty((chan)).uniform_(self.pl, self.ph) if self.random else self.mean[:chan]
-            if w < img_w and h < img_h:
-                top = random.randint(0, img_h - h)
-                left = random.randint(0, img_w - w)
-                if self.per_pixel:
-                    img[:, top:top + h, left:left + w] = torch.empty((chan, h, w)).uniform_(self.pl, self.ph)
-                else:
-                    img[:, top:top + h, left:left + w] = c
-                return img
-
-        return img

models/transforms.py

@@ -1,80 +0,0 @@
-import torch
-from torchvision import transforms
-from PIL import Image
-import math
-from models.random_erasing import RandomErasing
-
-DEFAULT_CROP_PCT = 0.875
-
-IMAGENET_DPN_MEAN = [124 / 255, 117 / 255, 104 / 255]
-IMAGENET_DPN_STD = [1 / (.0167 * 255)] * 3
-IMAGENET_DEFAULT_MEAN = [0.485, 0.456, 0.406]
-IMAGENET_DEFAULT_STD = [0.229, 0.224, 0.225]
-
-
-class LeNormalize(object):
-    """Normalize to -1..1 in Google Inception style
-    """
-    def __call__(self, tensor):
-        for t in tensor:
-            t.sub_(0.5).mul_(2.0)
-        return tensor
-
-
-def transforms_imagenet_train(
-        model_name,
-        img_size=224,
-        scale=(0.1, 1.0),
-        color_jitter=(0.4, 0.4, 0.4),
-        random_erasing=0.4):
-    if 'dpn' in model_name:
-        normalize = transforms.Normalize(
-            mean=IMAGENET_DPN_MEAN,
-            std=IMAGENET_DPN_STD)
-    elif 'inception' in model_name:
-        normalize = LeNormalize()
-    else:
-        normalize = transforms.Normalize(
-            mean=IMAGENET_DEFAULT_MEAN,
-            std=IMAGENET_DEFAULT_STD)
-
-    tfl = [
-        transforms.RandomResizedCrop(img_size, scale=scale),
-        transforms.RandomHorizontalFlip(),
-        transforms.ColorJitter(*color_jitter),
-        transforms.ToTensor()]
-    if random_erasing > 0.:
-        tfl.append(RandomErasing(random_erasing, per_pixel=True))
-    return transforms.Compose(tfl + [normalize])
-
-
-def transforms_imagenet_eval(model_name, img_size=224, crop_pct=None):
-    crop_pct = crop_pct or DEFAULT_CROP_PCT
-    if 'dpn' in model_name:
-        if crop_pct is None:
-            # Use default 87.5% crop for model's native img_size
-            # but use 100% crop for larger than native as it
-            # improves test time results across all models.
-            if img_size == 224:
-                scale_size = int(math.floor(img_size / DEFAULT_CROP_PCT))
-            else:
-                scale_size = img_size
-        else:
-            scale_size = int(math.floor(img_size / crop_pct))
-        normalize = transforms.Normalize(
-            mean=IMAGENET_DPN_MEAN,
-            std=IMAGENET_DPN_STD)
-    elif 'inception' in model_name:
-        scale_size = int(math.floor(img_size / crop_pct))
-        normalize = LeNormalize()
-    else:
-        scale_size = int(math.floor(img_size / crop_pct))
-        normalize = transforms.Normalize(
-            mean=IMAGENET_DEFAULT_MEAN,
-            std=IMAGENET_DEFAULT_STD)
-
-    return transforms.Compose([
-        transforms.Resize(scale_size, Image.BICUBIC),
-        transforms.CenterCrop(img_size),
-        transforms.ToTensor(),
-        normalize])

optim/__init__.py

@@ -0,0 +1,2 @@
+from optim.adabound import AdaBound
+from optim.nadam import Nadam

train.py

@@ -3,10 +3,10 @@ import time
 from collections import OrderedDict
 from datetime import datetime
 
-from dataset import Dataset
-from models import model_factory, transforms_imagenet_eval, transforms_imagenet_train
+from data import *
+from models import model_factory
 from utils import *
-from optim import nadam, adabound
+from optim import Nadam, AdaBound
 import scheduler
 
 import torch
@@ -95,24 +95,32 @@ def main():
 
     dataset_train = Dataset(
         os.path.join(args.data, 'train'),
-        transform=transforms_imagenet_train(args.model))
+        transform=transforms_imagenet_train())
 
     loader_train = data.DataLoader(
         dataset_train,
         batch_size=batch_size,
         shuffle=True,
-        num_workers=args.workers
+        num_workers=args.workers,
+        collate_fn=fast_collate
     )
+    loader_train = PrefetchLoader(
+        loader_train, random_erasing=True,
+        )
 
     dataset_eval = Dataset(
         os.path.join(args.data, 'validation'),
-        transform=transforms_imagenet_eval(args.model))
+        transform=transforms_imagenet_eval())
 
     loader_eval = data.DataLoader(
         dataset_eval,
         batch_size=4 * args.batch_size,
         shuffle=False,
-        num_workers=args.workers
+        num_workers=args.workers,
+        collate_fn=fast_collate,
+    )
+    loader_eval = PrefetchLoader(
+        loader_eval, random_erasing=False,
     )
 
     model = model_factory.create_model(
@@ -156,66 +164,11 @@ def main():
 
     train_loss_fn = validate_loss_fn = torch.nn.CrossEntropyLoss().cuda()
 
-    if args.opt.lower() == 'sgd':
-        optimizer = optim.SGD(
-            model.parameters(), lr=args.lr,
-            momentum=args.momentum, weight_decay=args.weight_decay, nesterov=True)
-    elif args.opt.lower() == 'adam':
-        optimizer = optim.Adam(
-            model.parameters(), lr=args.lr, weight_decay=args.weight_decay, eps=args.opt_eps)
-    elif args.opt.lower() == 'nadam':
-        optimizer = nadam.Nadam(
-            model.parameters(), lr=args.lr, weight_decay=args.weight_decay, eps=args.opt_eps)
-    elif args.opt.lower() == 'adabound':
-        optimizer = adabound.AdaBound(
-            model.parameters(), lr=args.lr / 1000, weight_decay=args.weight_decay, eps=args.opt_eps,
-            final_lr=args.lr)
-    elif args.opt.lower() == 'adadelta':
-        optimizer = optim.Adadelta(
-            model.parameters(), lr=args.lr, weight_decay=args.weight_decay, eps=args.opt_eps)
-    elif args.opt.lower() == 'rmsprop':
-        optimizer = optim.RMSprop(
-            model.parameters(), lr=args.lr, alpha=0.9, eps=args.opt_eps,
-            momentum=args.momentum, weight_decay=args.weight_decay)
-    else:
-        assert False and "Invalid optimizer"
-        exit(1)
-
-    #if optimizer_state is not None:
-    #    optimizer.load_state_dict(optimizer_state)
+    optimizer = create_optimizer(args, model.parameters())
+    if optimizer_state is not None:
+        optimizer.load_state_dict(optimizer_state)
 
-    num_epochs = args.epochs
-    if args.sched == 'cosine':
-        lr_scheduler = scheduler.CosineLRScheduler(
-            optimizer,
-            t_initial=args.epochs,
-            t_mul=1.0,
-            lr_min=1e-5,
-            decay_rate=args.decay_rate,
-            warmup_lr_init=1e-4,
-            warmup_t=3,
-            cycle_limit=1,
-            t_in_epochs=True,
-        )
-        num_epochs = lr_scheduler.get_cycle_length() + 10
-    elif args.sched == 'tanh':
-        lr_scheduler = scheduler.TanhLRScheduler(
-            optimizer,
-            t_initial=args.epochs,
-            t_mul=1.0,
-            lr_min=1e-5,
-            warmup_lr_init=.001,
-            warmup_t=3,
-            cycle_limit=1,
-            t_in_epochs=True,
-        )
-        num_epochs = lr_scheduler.get_cycle_length() + 10
-    else:
-        lr_scheduler = scheduler.StepLRScheduler(
-            optimizer,
-            decay_t=args.decay_epochs,
-            decay_rate=args.decay_rate,
-        )
+    lr_scheduler, num_epochs = create_scheduler(args, optimizer)
     print(num_epochs)
 
     saver = CheckpointSaver(checkpoint_dir=output_dir)
@@ -244,7 +197,6 @@ def main():
                 'state_dict': model.state_dict(),
                 'optimizer': optimizer.state_dict(),
                 'args': args,
-                'gp': args.gp,
                 },
                 epoch=epoch + 1,
                 metric=eval_metrics['eval_loss'])
@@ -271,12 +223,6 @@ def train_epoch(
         last_batch = batch_idx == last_idx
         data_time_m.update(time.time() - end)
 
-        input = input.cuda()
-        if isinstance(target, (tuple, list)):
-            target = [t.cuda() for t in target]
-        else:
-            target = target.cuda()
-
         output = model(input)
 
         loss = loss_fn(output, target)
@@ -286,6 +232,7 @@ def train_epoch(
         loss.backward()
         optimizer.step()
 
+        torch.cuda.synchronize()
         num_updates += 1
 
         batch_time_m.update(time.time() - end)
@@ -316,7 +263,7 @@ def train_epoch(
                     padding=0,
                     normalize=True)
 
-        if saver is not None and last_batch or batch_idx % args.recovery_interval == 0:
+        if saver is not None and last_batch or (batch_idx + 1) % args.recovery_interval == 0:
             save_epoch = epoch + 1 if last_batch else epoch
             saver.save_recovery({
                 'epoch': save_epoch,
@@ -324,7 +271,6 @@ def train_epoch(
                 'state_dict':  model.state_dict(),
                 'optimizer': optimizer.state_dict(),
                 'args': args,
-                'gp': args.gp,
                 },
                 epoch=save_epoch,
                 batch_idx=batch_idx)
@@ -351,12 +297,6 @@ def validate(model, loader, loss_fn, args):
         for batch_idx, (input, target) in enumerate(loader):
             last_batch = batch_idx == last_idx
 
-            input = input.cuda()
-            if isinstance(target, list):
-                target = target[0].cuda()
-            else:
-                target = target.cuda()
-
             output = model(input)
             if isinstance(output, (tuple, list)):
                 output = output[0]
@@ -367,12 +307,12 @@ def validate(model, loader, loss_fn, args):
                 output = output.unfold(0, reduce_factor, reduce_factor).mean(dim=2)
                 target = target[0:target.size(0):reduce_factor]
 
-            # calc loss
             loss = loss_fn(output, target)
-            losses_m.update(loss.item(), input.size(0))
-
-            # metrics
             prec1, prec5 = accuracy(output, target, topk=(1, 5))
+
+            torch.cuda.synchronize()
+
+            losses_m.update(loss.item(), input.size(0))
             prec1_m.update(prec1.item(), output.size(0))
             prec5_m.update(prec5.item(), output.size(0))
 
@@ -393,5 +333,69 @@ def validate(model, loader, loss_fn, args):
     return metrics
 
 
+def create_optimizer(args, parameters):
+    if args.opt.lower() == 'sgd':
+        optimizer = optim.SGD(
+            parameters, lr=args.lr,
+            momentum=args.momentum, weight_decay=args.weight_decay, nesterov=True)
+    elif args.opt.lower() == 'adam':
+        optimizer = optim.Adam(
+            parameters, lr=args.lr, weight_decay=args.weight_decay, eps=args.opt_eps)
+    elif args.opt.lower() == 'nadam':
+        optimizer = Nadam(
+            parameters, lr=args.lr, weight_decay=args.weight_decay, eps=args.opt_eps)
+    elif args.opt.lower() == 'adabound':
+        optimizer = AdaBound(
+            parameters, lr=args.lr / 100, weight_decay=args.weight_decay, eps=args.opt_eps,
+            final_lr=args.lr)
+    elif args.opt.lower() == 'adadelta':
+        optimizer = optim.Adadelta(
+            parameters, lr=args.lr, weight_decay=args.weight_decay, eps=args.opt_eps)
+    elif args.opt.lower() == 'rmsprop':
+        optimizer = optim.RMSprop(
+            parameters, lr=args.lr, alpha=0.9, eps=args.opt_eps,
+            momentum=args.momentum, weight_decay=args.weight_decay)
+    else:
+        assert False and "Invalid optimizer"
+        raise ValueError
+    return optimizer
+
+
+def create_scheduler(args, optimizer):
+    num_epochs = args.epochs
+    if args.sched == 'cosine':
+        lr_scheduler = scheduler.CosineLRScheduler(
+            optimizer,
+            t_initial=num_epochs,
+            t_mul=1.0,
+            lr_min=1e-5,
+            decay_rate=args.decay_rate,
+            warmup_lr_init=1e-4,
+            warmup_t=0,
+            cycle_limit=1,
+            t_in_epochs=True,
+        )
+        num_epochs = lr_scheduler.get_cycle_length() + 10
+    elif args.sched == 'tanh':
+        lr_scheduler = scheduler.TanhLRScheduler(
+            optimizer,
+            t_initial=num_epochs,
+            t_mul=1.0,
+            lr_min=1e-5,
+            warmup_lr_init=.001,
+            warmup_t=3,
+            cycle_limit=1,
+            t_in_epochs=True,
+        )
+        num_epochs = lr_scheduler.get_cycle_length() + 10
+    else:
+        lr_scheduler = scheduler.StepLRScheduler(
+            optimizer,
+            decay_t=args.decay_epochs,
+            decay_rate=args.decay_rate,
+        )
+    return lr_scheduler, num_epochs
+
+
 if __name__ == '__main__':
     main()