Merge branch 'vision-merge' into 'main'

Phase1 merge: vit optimizations + dataset enhancements + scaled_softmax kernel

See merge request ADLR/megatron-lm!378

megatron/arguments.py

@@ -518,6 +518,9 @@ def _add_initialization_args(parser):
     group.add_argument('--seed', type=int, default=1234,
                        help='Random seed used for python, numpy, '
                        'pytorch, and cuda.')
+    group.add_argument('--data-parallel-random-init', action='store_true',
+                       help='Enable random initialization of params '
+                       'across data parallel ranks')
     group.add_argument('--init-method-std', type=float, default=0.02,
                        help='Standard deviation of the zero mean normal '
                        'distribution used for weight initialization.')
@@ -835,11 +838,20 @@ def _add_vit_args(parser):
 
     group.add_argument('--num-classes', type=int, default=1000,
                        help='num of classes in vision classificaiton task')
-    group.add_argument('--img-dim', type=int, default=224,
-                       help='Image size for vision classification task')
+    group.add_argument('--img-h', type=int, default=224,
+                       help='Image height for vision classification task')
+    group.add_argument('--img-w', type=int, default=224,
+                       help='Image height for vision classification task')
     group.add_argument('--num-channels', type=int, default=3,
                        help='Number of channels in input image data')
     group.add_argument('--patch-dim', type=int, default=16,
                        help='patch dimension used in vit')
+    group.add_argument('--classes-fraction', type=float, default=1.0,
+                       help='training with fraction of classes.')
+    group.add_argument('--data-per-class-fraction', type=float, default=1.0,
+                       help='training with fraction of data per class.')
+    group.add_argument('--no-data-sharding', action='store_false',
+                       help='Disable data sharding.',
+                       dest='data_sharding')
 
     return parser

megatron/checkpointing.py

@@ -65,6 +65,8 @@ def check_checkpoint_args(checkpoint_args):
         _compare('make_vocab_size_divisible_by')
         _compare('padded_vocab_size')
         _compare('tokenizer_type')
+    if args.data_parallel_random_init:
+        _compare('data_parallel_random_init')
     if get_checkpoint_version() < 3.0:
         _compare('tensor_model_parallel_size',
                  old_arg_name='model_parallel_size')
@@ -72,7 +74,6 @@ def check_checkpoint_args(checkpoint_args):
         _compare('tensor_model_parallel_size')
         _compare('pipeline_model_parallel_size')
 
-
 def ensure_directory_exists(filename):
     """Build filename's path if it does not already exists."""
     dirname = os.path.dirname(filename)
@@ -140,6 +141,32 @@ def read_metadata(tracker_filename):
     return max_iter, release
 
 
+def get_rng_state():
+    """ collect rng state across data parallel ranks """
+    args = get_args()
+    rng_state = {
+        'random_rng_state': random.getstate(),
+        'np_rng_state': np.random.get_state(),
+        'torch_rng_state': torch.get_rng_state(),
+        'cuda_rng_state': torch.cuda.get_rng_state(),
+        'rng_tracker_states': mpu.get_cuda_rng_tracker().get_states()}
+
+    rng_state_list = None
+    if torch.distributed.is_initialized() and \
+            mpu.get_data_parallel_world_size() > 1 and \
+            args.data_parallel_random_init:
+        rng_state_list = \
+            [None for i in range(mpu.get_data_parallel_world_size())]
+        torch.distributed.all_gather_object(
+            rng_state_list,
+            rng_state,
+            group=mpu.get_data_parallel_group())
+    else:
+        rng_state_list = [rng_state]
+
+    return rng_state_list
+
+
 def save_checkpoint(iteration, model, optimizer, lr_scheduler):
     """Save a model checkpoint."""
     args = get_args()
@@ -150,6 +177,9 @@ def save_checkpoint(iteration, model, optimizer, lr_scheduler):
     print_rank_0('saving checkpoint at iteration {:7d} to {}'.format(
         iteration, args.save))
 
+    # collect rng state across data parallel ranks
+    rng_state = get_rng_state()
+
     if not torch.distributed.is_initialized() or mpu.get_data_parallel_rank() == 0:
 
         # Arguments, iteration, and model.
@@ -173,12 +203,7 @@ def save_checkpoint(iteration, model, optimizer, lr_scheduler):
 
         # RNG states.
         if not args.no_save_rng:
-            state_dict['random_rng_state'] = random.getstate()
-            state_dict['np_rng_state'] = np.random.get_state()
-            state_dict['torch_rng_state'] = torch.get_rng_state()
-            state_dict['cuda_rng_state'] = torch.cuda.get_rng_state()
-            state_dict['rng_tracker_states'] \
-                = mpu.get_cuda_rng_tracker().get_states()
+            state_dict["rng_state"] = rng_state
 
         # Save.
         checkpoint_name = get_checkpoint_name(args.save, iteration)
@@ -381,15 +406,32 @@ def load_checkpoint(model, optimizer, lr_scheduler, load_arg='load', strict=True
     # rng states.
     if not release and not args.finetune and not args.no_load_rng:
         try:
-            random.setstate(state_dict['random_rng_state'])
-            np.random.set_state(state_dict['np_rng_state'])
-            torch.set_rng_state(state_dict['torch_rng_state'])
-            torch.cuda.set_rng_state(state_dict['cuda_rng_state'])
-            # Check for empty states array
-            if not state_dict['rng_tracker_states']:
-                raise KeyError
-            mpu.get_cuda_rng_tracker().set_states(
-                state_dict['rng_tracker_states'])
+            if 'rng_state' in state_dict:
+                # access rng_state for data parallel rank
+                if args.data_parallel_random_init:
+
+                    rng_state = state_dict['rng_state'][mpu.get_data_parallel_rank()]
+                else:
+                    rng_state = state_dict['rng_state'][0]
+                random.setstate(rng_state['random_rng_state'])
+                np.random.set_state(rng_state['np_rng_state'])
+                torch.set_rng_state(rng_state['torch_rng_state'])
+                torch.cuda.set_rng_state(rng_state['cuda_rng_state'])
+                # Check for empty states array
+                if not rng_state['rng_tracker_states']:
+                    raise KeyError
+                mpu.get_cuda_rng_tracker().set_states(
+                    rng_state['rng_tracker_states'])
+            else:  # backward compatability
+                random.setstate(state_dict['random_rng_state'])
+                np.random.set_state(state_dict['np_rng_state'])
+                torch.set_rng_state(state_dict['torch_rng_state'])
+                torch.cuda.set_rng_state(state_dict['cuda_rng_state'])
+                # Check for empty states array
+                if not state_dict['rng_tracker_states']:
+                    raise KeyError
+                mpu.get_cuda_rng_tracker().set_states(
+                    state_dict['rng_tracker_states'])
         except KeyError:
             print_rank_0('Unable to load rng state from checkpoint {}. '
                          'Specify --no-load-rng or --finetune to prevent '

megatron/data/data_samplers.py

@@ -16,8 +16,10 @@
 """Dataloaders."""
 
 
-import torch
 import random
+import torch
+import numpy as np
+from torch.utils.data import Dataset
 from megatron import get_args
 from megatron import mpu
 
@@ -39,11 +41,13 @@ def build_pretraining_data_loader(dataset, consumed_samples):
             data_parallel_size=mpu.get_data_parallel_world_size())
     elif args.dataloader_type == 'cyclic':
         batch_sampler = MegatronPretrainingRandomSampler(
+            dataset,
             total_samples=len(dataset),
             consumed_samples=consumed_samples,
             micro_batch_size=args.micro_batch_size,
             data_parallel_rank=mpu.get_data_parallel_rank(),
-            data_parallel_size=mpu.get_data_parallel_world_size())
+            data_parallel_size=mpu.get_data_parallel_world_size(),
+            data_sharding=args.data_sharding)
     else:
         raise Exception('{} dataloader type is not supported.'.format(
                 args.dataloader_type))
@@ -103,16 +107,40 @@ class MegatronPretrainingSampler:
             yield batch[start_idx:end_idx]
 
 
+class RandomSeedDataset(Dataset):
+
+    def __init__(self, dataset):
+        args = get_args()
+        self.base_seed = args.seed
+        self.curr_seed = args.seed
+        self.dataset = dataset
+
+    def __len__(self):
+        return len(self.dataset)
+
+    def set_epoch(self, epoch):
+        self.curr_seed = self.base_seed + epoch
+
+    def __getitem__(self, idx):
+        seed = idx + self.curr_seed
+        torch.manual_seed(seed)
+        random.seed(seed)
+        np.random.seed(seed)
+        return self.dataset[idx]
+
+
 class MegatronPretrainingRandomSampler:
 
-    def __init__(self, total_samples, consumed_samples, micro_batch_size,
-                 data_parallel_rank, data_parallel_size):
+    def __init__(self, dataset, total_samples, consumed_samples, micro_batch_size,
+                 data_parallel_rank, data_parallel_size, data_sharding):
         # Keep a copy of input params for later use.
+        self.dataset = dataset
         self.total_samples = total_samples
         self.consumed_samples = consumed_samples
         self.micro_batch_size = micro_batch_size
         self.data_parallel_rank = data_parallel_rank
         self.data_parallel_size = data_parallel_size
+        self.data_sharding = data_sharding
         self.micro_batch_times_data_parallel_size = \
             self.micro_batch_size * data_parallel_size
         self.last_batch_size = \
@@ -136,16 +164,30 @@ class MegatronPretrainingRandomSampler:
         current_epoch_samples = self.consumed_samples % active_total_samples
         assert current_epoch_samples % self.micro_batch_times_data_parallel_size == 0
 
+        if isinstance(self.dataset, RandomSeedDataset):
+            self.dataset.set_epoch(self.epoch)
+
         # data sharding and random sampling
-        bucket_size = (self.total_samples // self.micro_batch_times_data_parallel_size) \
-                       * self.micro_batch_size
-        bucket_offset = current_epoch_samples // self.data_parallel_size
-        start_idx = self.data_parallel_rank * bucket_size
-        
-        g = torch.Generator()
-        g.manual_seed(self.epoch)
-        random_idx = torch.randperm(bucket_size, generator=g).tolist()
-        idx_range = [start_idx + x for x in random_idx[bucket_offset:]]
+        if self.data_sharding:
+            bucket_size = (self.total_samples // self.micro_batch_times_data_parallel_size) \
+                           * self.micro_batch_size
+            bucket_offset = current_epoch_samples // self.data_parallel_size
+            start_idx = self.data_parallel_rank * bucket_size
+            
+            g = torch.Generator()
+            g.manual_seed(self.epoch)
+            random_idx = torch.randperm(bucket_size, generator=g).tolist()
+            idx_range = [start_idx + x for x in random_idx[bucket_offset:]]
+        else:
+            full_bucket_size = (self.total_samples // self.micro_batch_size) \
+                                * self.micro_batch_size
+            full_bucket_offset = current_epoch_samples
+            g = torch.Generator()
+            g.manual_seed(self.epoch)
+            idx_range_total = \
+                torch.randperm(full_bucket_size, generator=g).tolist()
+            idx_range_active = idx_range_total[full_bucket_offset:]
+            idx_range = idx_range_active[self.data_parallel_rank::self.data_parallel_size]
 
         batch = []
         # Last batch if not complete will be dropped.

megatron/data/image_folder.py

+# BSD 3-Clause License
+#
+# Copyright (c) Soumith Chintala 2016, 
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+#
+# * Neither the name of the copyright holder nor the names of its
+#   contributors may be used to endorse or promote products derived from
+#   this software without specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# code taken from 
+# https://github.com/pytorch/vision/blob/main/torchvision/datasets/folder.py
+# added support for classes_fraction and data_per_class_fraction
+
+from torchvision.datasets import VisionDataset
+from PIL import Image
+
+import os
+import os.path
+from typing import Any, Callable, cast, Dict, List, Optional, Tuple
+import numpy as np
+
+def has_file_allowed_extension(filename: str, extensions: Tuple[str, ...]) -> bool:
+    """Checks if a file is an allowed extension.
+    Args:
+        filename (string): path to a file
+        extensions (tuple of strings): extensions to consider (lowercase)
+    Returns:
+        bool: True if the filename ends with one of given extensions
+    """
+    return filename.lower().endswith(extensions)
+
+
+def is_image_file(filename: str) -> bool:
+    """Checks if a file is an allowed image extension.
+    Args:
+        filename (string): path to a file
+    Returns:
+        bool: True if the filename ends with a known image extension
+    """
+    return has_file_allowed_extension(filename, IMG_EXTENSIONS)
+
+
+def make_dataset(
+    directory: str,
+    class_to_idx: Dict[str, int],
+    data_per_class_fraction: float,
+    extensions: Optional[Tuple[str, ...]] = None,
+    is_valid_file: Optional[Callable[[str], bool]] = None,
+) -> List[Tuple[str, int]]:
+    """Generates a list of samples of a form (path_to_sample, class).
+    Args:
+        directory (str): root dataset directory
+        class_to_idx (Dict[str, int]): dictionary mapping class name to class index
+        extensions (optional): A list of allowed extensions.
+            Either extensions or is_valid_file should be passed. Defaults to None.
+        is_valid_file (optional): A function that takes path of a file
+            and checks if the file is a valid file
+            (used to check of corrupt files) both extensions and
+            is_valid_file should not be passed. Defaults to None.
+    Raises:
+        ValueError: In case ``extensions`` and ``is_valid_file`` are None or both are not None.
+    Returns:
+        List[Tuple[str, int]]: samples of a form (path_to_sample, class)
+    """
+    instances = []
+    directory = os.path.expanduser(directory)
+    both_none = extensions is None and is_valid_file is None
+    both_something = extensions is not None and is_valid_file is not None
+    if both_none or both_something:
+        raise ValueError("Both extensions and is_valid_file cannot be None or not None at the same time")
+    if extensions is not None:
+        def is_valid_file(x: str) -> bool:
+            return has_file_allowed_extension(x, cast(Tuple[str, ...], extensions))
+    is_valid_file = cast(Callable[[str], bool], is_valid_file)
+    for target_class in sorted(class_to_idx.keys()):
+        class_index = class_to_idx[target_class]
+        target_dir = os.path.join(directory, target_class)
+        if not os.path.isdir(target_dir):
+            continue
+        local_instances = []
+        for root, _, fnames in sorted(os.walk(target_dir, followlinks=True)):
+            for fname in sorted(fnames):
+                path = os.path.join(root, fname)
+                if is_valid_file(path):
+                    item = path, class_index
+                    local_instances.append(item)
+
+        instances.extend(local_instances[0:int(len(local_instances) * data_per_class_fraction)])
+
+    return instances
+
+
+class DatasetFolder(VisionDataset):
+    """A generic data loader where the samples are arranged in this way: ::
+        root/class_x/xxx.ext
+        root/class_x/xxy.ext
+        root/class_x/[...]/xxz.ext
+        root/class_y/123.ext
+        root/class_y/nsdf3.ext
+        root/class_y/[...]/asd932_.ext
+    Args:
+        root (string): Root directory path.
+        loader (callable): A function to load a sample given its path.
+        extensions (tuple[string]): A list of allowed extensions.
+            both extensions and is_valid_file should not be passed.
+        transform (callable, optional): A function/transform that takes in
+            a sample and returns a transformed version.
+            E.g, ``transforms.RandomCrop`` for images.
+        target_transform (callable, optional): A function/transform that takes
+            in the target and transforms it.
+        is_valid_file (callable, optional): A function that takes path of a file
+            and check if the file is a valid file (used to check of corrupt files)
+            both extensions and is_valid_file should not be passed.
+     Attributes:
+        classes (list): List of the class names sorted alphabetically.
+        class_to_idx (dict): Dict with items (class_name, class_index).
+        samples (list): List of (sample path, class_index) tuples
+        targets (list): The class_index value for each image in the dataset
+    """
+
+    def __init__(
+            self,
+            root: str,
+            loader: Callable[[str], Any],
+            extensions: Optional[Tuple[str, ...]] = None,
+            transform: Optional[Callable] = None,
+            target_transform: Optional[Callable] = None,
+            classes_fraction=1.0,
+            data_per_class_fraction=1.0,
+            is_valid_file: Optional[Callable[[str], bool]] = None,
+    ) -> None:
+        super(DatasetFolder, self).__init__(root, transform=transform,
+                                            target_transform=target_transform)
+        self.classes_fraction = classes_fraction
+        self.data_per_class_fraction = data_per_class_fraction
+        classes, class_to_idx = self._find_classes(self.root)
+        samples = self.make_dataset(self.root,
+                                    class_to_idx,
+                                    self.data_per_class_fraction,
+                                    extensions,
+                                    is_valid_file)
+        if len(samples) == 0:
+            msg = "Found 0 files in subfolders of: {}\n".format(self.root)
+            if extensions is not None:
+                msg += "Supported extensions are: {}".format(",".join(extensions))
+            raise RuntimeError(msg)
+
+        self.loader = loader
+        self.extensions = extensions
+        self.total = len(samples)
+        self.classes = classes
+        self.class_to_idx = class_to_idx
+        self.samples = samples
+        self.targets = [s[1] for s in samples]
+
+    @staticmethod
+    def make_dataset(
+        directory: str,
+        class_to_idx: Dict[str, int],
+        data_per_class_fraction: float,
+        extensions: Optional[Tuple[str, ...]] = None,
+        is_valid_file: Optional[Callable[[str], bool]] = None,
+    ) -> List[Tuple[str, int]]:
+        return make_dataset(directory,
+                            class_to_idx,
+                            data_per_class_fraction,
+                            extensions=extensions,
+                            is_valid_file=is_valid_file)
+
+    def _find_classes(self, dir: str) -> Tuple[List[str], Dict[str, int]]:
+        """
+        Finds the class folders in a dataset.
+        Args:
+            dir (string): Root directory path.
+        Returns:
+            tuple: (classes, class_to_idx) where classes are relative to (dir), and class_to_idx is a dictionary.
+        Ensures:
+            No class is a subdirectory of another.
+        """
+        all_classes = [d.name for d in os.scandir(dir) if d.is_dir()]
+        classes = all_classes[0:int(len(all_classes) * self.classes_fraction)]
+        classes.sort()
+        class_to_idx = {cls_name: i for i, cls_name in enumerate(classes)}
+        return classes, class_to_idx
+
+    def __getitem__(self, index: int) -> Tuple[Any, Any]:
+        """
+        Args:
+            index (int): Index
+        Returns:
+            tuple: (sample, target) where target is class_index of the target class.
+        """
+        curr_index = index
+        for x in range(self.total):
+            try:
+                path, target = self.samples[curr_index]
+                sample = self.loader(path)
+                break
+            except Exception as e:
+                curr_index = np.random.randint(0, self.total)
+
+        if self.transform is not None:
+            sample = self.transform(sample)
+        if self.target_transform is not None:
+            target = self.target_transform(target)
+
+        return sample, target
+
+    def __len__(self) -> int:
+        return len(self.samples)
+
+
+IMG_EXTENSIONS = ('.jpg', '.jpeg', '.png', '.ppm', '.bmp', '.pgm', '.tif', '.tiff', '.webp')
+
+
+def pil_loader(path: str) -> Image.Image:
+    # open path as file to avoid ResourceWarning (https://github.com/python-pillow/Pillow/issues/835)
+    with open(path, 'rb') as f:
+        img = Image.open(f)
+        return img.convert('RGB')
+
+
+# TODO: specify the return type
+def accimage_loader(path: str) -> Any:
+    import accimage
+    try:
+        return accimage.Image(path)
+    except IOError:
+        # Potentially a decoding problem, fall back to PIL.Image
+        return pil_loader(path)
+
+
+def default_loader(path: str) -> Any:
+    from torchvision import get_image_backend
+    if get_image_backend() == 'accimage':
+        return accimage_loader(path)
+    else:
+        return pil_loader(path)
+
+
+class ImageFolder(DatasetFolder):
+    """A generic data loader where the images are arranged in this way: ::
+        root/dog/xxx.png
+        root/dog/xxy.png
+        root/dog/[...]/xxz.png
+        root/cat/123.png
+        root/cat/nsdf3.png
+        root/cat/[...]/asd932_.png
+    Args:
+        root (string): Root directory path.
+        transform (callable, optional): A function/transform that  takes in an PIL image
+            and returns a transformed version. E.g, ``transforms.RandomCrop``
+        target_transform (callable, optional): A function/transform that takes in the
+            target and transforms it.
+        loader (callable, optional): A function to load an image given its path.
+        is_valid_file (callable, optional): A function that takes path of an Image file
+            and check if the file is a valid file (used to check of corrupt files)
+     Attributes:
+        classes (list): List of the class names sorted alphabetically.
+        class_to_idx (dict): Dict with items (class_name, class_index).
+        imgs (list): List of (image path, class_index) tuples
+    """
+
+    def __init__(
+            self,
+            root: str,
+            transform: Optional[Callable] = None,
+            target_transform: Optional[Callable] = None,
+            classes_fraction=1.0,
+            data_per_class_fraction=1.0,
+            loader: Callable[[str], Any] = default_loader,
+            is_valid_file: Optional[Callable[[str], bool]] = None,
+    ):
+        super(ImageFolder, self).__init__(root, loader, IMG_EXTENSIONS if is_valid_file is None else None,
+                                          transform=transform,
+                                          target_transform=target_transform,
+                                          classes_fraction=classes_fraction,
+                                          data_per_class_fraction=data_per_class_fraction,
+                                          is_valid_file=is_valid_file)
+        self.imgs = self.samples
+

megatron/data/vit_dataset.py

@@ -13,46 +13,67 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import os
+import random
+import numpy as np
 import torch
-from torchvision import datasets, transforms
+import torchvision.transforms as T
+from torchvision import datasets
+from megatron import get_args
+from megatron.data.image_folder import ImageFolder
 from megatron.data.autoaugment import ImageNetPolicy
+from megatron.data.data_samplers import RandomSeedDataset
 
+class ClassificationTransform():
+    def __init__(self, image_size, train=True):
+        args = get_args()
+        assert args.fp16 or args.bf16
+        self.data_type = torch.half if args.fp16 else torch.bfloat16
+        if train:
+            self.transform = T.Compose([
+                T.RandomResizedCrop(image_size),
+                T.RandomHorizontalFlip(),
+                T.ColorJitter(0.4, 0.4, 0.4, 0.1),
+                ImageNetPolicy(),
+                T.ToTensor(),
+                T.Normalize((0.485, 0.456, 0.406), (0.229, 0.224, 0.225)),
+                T.ConvertImageDtype(self.data_type)
+            ])
+        else:
+            self.transform = T.Compose([
+                T.Resize(image_size),
+                T.CenterCrop(image_size),
+                T.ToTensor(),
+                T.Normalize((0.485, 0.456, 0.406), (0.229, 0.224, 0.225)),
+                T.ConvertImageDtype(self.data_type)
+            ])
 
-def build_train_valid_datasets(data_path, crop_size=224, color_jitter=True):
+    def __call__(self, input):
+        output = self.transform(input)
+        return output
+
+
+
+def build_train_valid_datasets(data_path, image_size=224):
+    args = get_args()
+    train_transform = ClassificationTransform(image_size)
+    val_transform = ClassificationTransform(image_size, train=False)
 
     # training dataset
-    train_data_path = os.path.join(data_path[0], "train")
-    normalize = transforms.Normalize(mean=[0.5, 0.5, 0.5], std=[0.5, 0.5, 0.5])
-    process = [
-        transforms.RandomResizedCrop(crop_size),
-        transforms.RandomHorizontalFlip(),
-    ]
-    if color_jitter:
-        process += [
-            transforms.ColorJitter(
-                brightness=0.4, contrast=0.4, saturation=0.4, hue=0.1
-            )
-        ]
-    fp16_t = transforms.ConvertImageDtype(torch.half)
-    process += [ImageNetPolicy(), transforms.ToTensor(), normalize, fp16_t]
-    transform_train = transforms.Compose(process)
-    train_data = datasets.ImageFolder(
-        root=train_data_path, transform=transform_train
+    train_data_path = data_path[0]
+    train_data = ImageFolder(
+        root=train_data_path,
+        transform=train_transform,
+        classes_fraction=args.classes_fraction,
+        data_per_class_fraction=args.data_per_class_fraction
     )
+    train_data = RandomSeedDataset(train_data)
 
     # validation dataset
-    val_data_path = os.path.join(data_path[0], "val")
-    transform_val = transforms.Compose(
-        [
-            transforms.Resize(crop_size),
-            transforms.CenterCrop(crop_size),
-            transforms.ToTensor(),
-            normalize,
-            fp16_t
-        ]
-    )
-    val_data = datasets.ImageFolder(
-        root=val_data_path, transform=transform_val
+    val_data_path = data_path[1]
+    val_data = ImageFolder(
+        root=val_data_path,
+        transform=val_transform
     )
+    val_data = RandomSeedDataset(val_data)
 
     return train_data, val_data

megatron/fused_kernels/__init__.py

@@ -78,6 +78,12 @@ def load(args):
         scaled_masked_softmax_cuda = _cpp_extention_load_helper(
             "scaled_masked_softmax_cuda", sources, extra_cuda_flags)
 
+        # Softmax
+        sources=[srcpath / 'scaled_softmax.cpp',
+                 srcpath / 'scaled_softmax_cuda.cu']
+        scaled_softmax_cuda = _cpp_extention_load_helper(
+            "scaled_softmax_cuda", sources, extra_cuda_flags)
+
     # =================================
     # Mixed precision fused layer norm.
     # =================================

megatron/fused_kernels/scaled_masked_softmax.h

@@ -90,6 +90,117 @@ __device__ __forceinline__ void warp_reduce(acc_t* sum) {
     }
 }
 
+
+/*
+ * Extended softmax (from native aten pytorch) with following additional features
+ * 1) input scaling
+ */	
+template <typename input_t, typename output_t, typename acc_t, int log2_elements>
+__global__ void scaled_softmax_warp_forward(
+    output_t *dst, 
+    const input_t *src,
+    const acc_t scale, 
+    int micro_batch_size, 
+    int element_count)
+{
+    // WARP_SIZE and WARP_BATCH must match the return values batches_per_warp and 
+    // warp_size of method warp_softmax_forward_kernel.
+    constexpr int next_power_of_two = 1 << log2_elements;
+    constexpr int WARP_SIZE = (next_power_of_two < C10_WARP_SIZE) ? next_power_of_two : C10_WARP_SIZE;
+    constexpr int WARP_ITERATIONS = next_power_of_two / WARP_SIZE;
+    constexpr int WARP_BATCH = (next_power_of_two <= 128) ? 2 : 1;
+    constexpr int ELEMENTS_PER_LDG_STG = (WARP_ITERATIONS < 4) ? 1 : 4;
+
+    // blockDim/threadIdx = (WARP_SIZE, WARPS_PER_BLOCK, )
+    // gridDim/blockIdx = (seq_len, attn_heads, batches) 
+    int first_batch = (blockDim.y * (blockIdx.x + gridDim.x * (blockIdx.y + gridDim.y * blockIdx.z))+ threadIdx.y) * WARP_BATCH;
+
+    // micro_batch_size might not be a multiple of WARP_BATCH. Check how
+    // many batches have to computed within this WARP.
+    int local_batches = micro_batch_size - first_batch;
+    if (local_batches > WARP_BATCH)
+        local_batches = WARP_BATCH;
+
+    // there might be multiple batches per warp. compute the index within the batch
+    int local_idx = threadIdx.x;
+
+    src += first_batch * element_count + ELEMENTS_PER_LDG_STG * local_idx;
+    dst += first_batch * element_count + ELEMENTS_PER_LDG_STG * local_idx;
+
+    // load data from global memory
+    acc_t elements[WARP_BATCH][WARP_ITERATIONS];
+    input_t temp_data[ELEMENTS_PER_LDG_STG];
+    #pragma unroll
+    for (int i = 0;  i < WARP_BATCH;  ++i) {
+        int batch_element_count = (i >= local_batches) ? 0 : element_count;
+
+        #pragma unroll
+        for (int it = 0;  it < WARP_ITERATIONS;  it+=ELEMENTS_PER_LDG_STG) {
+            int element_index = ELEMENTS_PER_LDG_STG * local_idx + it * WARP_SIZE;
+
+            if (element_index < batch_element_count) {
+                int itr_idx = i*element_count+it*WARP_SIZE;
+                copy_vector<input_t, ELEMENTS_PER_LDG_STG>(temp_data, src + itr_idx);
+
+                #pragma unroll
+                for (int element = 0; element < ELEMENTS_PER_LDG_STG; ++element) {
+                    elements[i][it + element] = (acc_t)temp_data[element] * scale;
+                }
+            } else {
+                #pragma unroll
+                for (int element = 0; element < ELEMENTS_PER_LDG_STG; ++element) {
+                    elements[i][it + element] = -std::numeric_limits<acc_t>::infinity();
+                }
+            }
+        }
+    }
+
+    // compute max_value
+    acc_t max_value[WARP_BATCH];
+    #pragma unroll
+    for (int i = 0;  i < WARP_BATCH;  ++i) {
+        max_value[i] = elements[i][0];
+        #pragma unroll
+        for (int it = 1;  it < WARP_ITERATIONS;  ++it) {
+            max_value[i] = (max_value[i] > elements[i][it]) ? max_value[i] : elements[i][it];
+        }
+    }
+    warp_reduce<acc_t, WARP_BATCH, WARP_SIZE, Max>(max_value);
+
+    acc_t sum[WARP_BATCH] { 0.0f };
+    #pragma unroll
+    for (int i = 0;  i < WARP_BATCH;  ++i) {
+        #pragma unroll
+        for (int it = 0;  it < WARP_ITERATIONS;  ++it) {
+            elements[i][it] = std::exp((elements[i][it] - max_value[i]));
+            sum[i] += elements[i][it];
+        }
+    }
+    warp_reduce<acc_t, WARP_BATCH, WARP_SIZE, Add>(sum);
+
+    // store result
+    output_t out[ELEMENTS_PER_LDG_STG];
+    #pragma unroll
+    for (int i = 0;  i < WARP_BATCH;  ++i) {
+        if (i >= local_batches)
+            break;
+        #pragma unroll
+        for (int it = 0;  it < WARP_ITERATIONS;  it+=ELEMENTS_PER_LDG_STG) {
+            int element_index = ELEMENTS_PER_LDG_STG * local_idx + it * WARP_SIZE;
+            if (element_index < element_count) {
+                #pragma unroll
+                for (int element = 0; element < ELEMENTS_PER_LDG_STG; ++element) {
+                    out[element] = elements[i][it + element] / sum[i];
+                }
+                copy_vector<output_t, ELEMENTS_PER_LDG_STG>(dst + i * element_count + it * WARP_SIZE, out);  
+            } else {
+                break;
+            } 
+        }
+    }
+}
+
+
 /*
  * Extended softmax (from native aten pytorch) with following additional features
  * 1) input scaling
@@ -326,6 +437,98 @@ int get_batch_per_block(int query_seq_len, int key_seq_len, int batches, int att
     return batches_per_block;
 }
 
+template<typename input_t, typename output_t, typename acc_t>
+void dispatch_scaled_softmax_forward(
+    output_t *dst, 
+    const input_t *src, 
+    const input_t scale, 
+    int query_seq_len, 
+    int key_seq_len, 
+    int batches,
+    int attn_heads)
+{
+    TORCH_INTERNAL_ASSERT(key_seq_len >= 0 && key_seq_len <= 4096 );
+    if (key_seq_len == 0) {
+        return;
+    } else {
+        int log2_elements = log2_ceil(key_seq_len);
+        const int next_power_of_two = 1 << log2_elements;
+        int batch_count = batches * attn_heads * query_seq_len;
+
+        // This value must match the WARP_SIZE constexpr value computed inside softmax_warp_forward.
+        int warp_size = (next_power_of_two < C10_WARP_SIZE) ? next_power_of_two : C10_WARP_SIZE;
+
+        // This value must match the WARP_BATCH constexpr value computed inside softmax_warp_forward.
+        int batches_per_warp = (next_power_of_two <= 128) ? 2 : 1;
+
+        // use 128 threads per block to maximimize gpu utilization
+        constexpr int threads_per_block = 128;
+
+        int warps_per_block = (threads_per_block / warp_size);
+        int batches_per_block = warps_per_block * batches_per_warp;
+        TORCH_INTERNAL_ASSERT(query_seq_len%batches_per_block == 0);
+        dim3 blocks(query_seq_len/batches_per_block, attn_heads, batches);
+        dim3 threads(warp_size, warps_per_block, 1);
+        // Launch code would be more elegant if C++ supported FOR CONSTEXPR
+        switch (log2_elements) {
+            case 0: // 1
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 0>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 1: // 2
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 1>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 2: // 4
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 2>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 3: // 8
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 3>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 4: // 16
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 4>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 5: // 32
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 5>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 6: // 64
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 6>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 7: // 128
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 7>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 8: // 256
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 8>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 9: // 512
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 9>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 10: // 1024
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 10>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 11: // 2048
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 11>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            case 12: // 4096
+                scaled_softmax_warp_forward<input_t, output_t, acc_t, 12>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, scale, batch_count, key_seq_len);
+                break;
+            default:
+                break;
+        }
+    }
+}
+
 template<typename input_t, typename output_t, typename acc_t>
 void dispatch_scaled_masked_softmax_forward(
     output_t *dst, 
@@ -338,7 +541,7 @@ void dispatch_scaled_masked_softmax_forward(
     int attn_heads,
     int pad_batches)
 {
-    TORCH_INTERNAL_ASSERT(key_seq_len >= 0 && key_seq_len <= 2048 );
+    TORCH_INTERNAL_ASSERT(key_seq_len >= 0 && key_seq_len <= 4096 );
     if (key_seq_len == 0) {
         return;
     } else {
@@ -410,6 +613,10 @@ void dispatch_scaled_masked_softmax_forward(
                 scaled_masked_softmax_warp_forward<input_t, output_t, acc_t, 11>
                     <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, mask, scale, batch_count, key_seq_len, pad_batches);
                 break;
+            case 12: // 4096
+                scaled_masked_softmax_warp_forward<input_t, output_t, acc_t, 12>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(dst, src, mask, scale, batch_count, key_seq_len, pad_batches);
+                break;
             default:
                 break;
         }
@@ -427,7 +634,7 @@ void dispatch_scaled_masked_softmax_backward(
     int batches,
     int attn_heads)
 {
-    TORCH_INTERNAL_ASSERT( key_seq_len >= 0 && key_seq_len <= 2048 );
+    TORCH_INTERNAL_ASSERT( key_seq_len >= 0 && key_seq_len <= 4096 );
     if (key_seq_len == 0) {
        return;
     } else {
@@ -498,6 +705,11 @@ void dispatch_scaled_masked_softmax_backward(
                 scaled_masked_softmax_warp_backward<input_t, output_t, acc_t, 11>
                     <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(grad_input, grad, output, scale, batch_count, key_seq_len);
                 break;
+			case 12: // 4096
+                scaled_masked_softmax_warp_backward<input_t, output_t, acc_t, 12>
+                    <<<blocks, threads, 0, at::cuda::getCurrentCUDAStream()>>>(grad_input, grad, output, scale, batch_count, key_seq_len);
+                break;
+
             default:
                 break;
         }

megatron/fused_kernels/scaled_masked_softmax_cuda.cu

@@ -44,7 +44,7 @@ torch::Tensor fwd_cuda(
   const int attn_heads = input.size(1);
   const int query_seq_len = input.size(2);
   const int key_seq_len = input.size(3);
-  TORCH_INTERNAL_ASSERT(key_seq_len <= 2048);
+  TORCH_INTERNAL_ASSERT(key_seq_len <= 4096);
   TORCH_INTERNAL_ASSERT(query_seq_len > 1);
   TORCH_INTERNAL_ASSERT(pad_batches == 1 || pad_batches == batches);
   TORCH_INTERNAL_ASSERT(mask.size(1) == 1);

megatron/fused_kernels/scaled_softmax.cpp

+/* coding=utf-8
+ * Copyright (c) 2020, 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.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <cuda_fp16.h>
+#include <torch/extension.h>
+#include <vector>
+
+namespace multihead_attn {
+namespace fused_softmax {
+namespace scaled_softmax {
+
+torch::Tensor fwd_cuda(
+    torch::Tensor const& input, 
+    float scale_factor);
+
+torch::Tensor bwd_cuda(
+    torch::Tensor const& output_grads, 
+    torch::Tensor const& softmax_results,
+    float scale_factor);
+
+torch::Tensor fwd(
+    torch::Tensor const& input,
+    float scale_factor) {
+  AT_ASSERTM(input.dim() == 4, "expected 4D tensor");
+  AT_ASSERTM((input.scalar_type() == at::ScalarType::Half) ||
+	     (input.scalar_type() == at::ScalarType::BFloat16), 
+      "Only fp16 and bf16 are supported");
+
+  return fwd_cuda(input, scale_factor);
+}
+
+torch::Tensor bwd(
+    torch::Tensor const& output_grads, 
+    torch::Tensor const& softmax_results,
+    float scale_factor) {
+
+  AT_ASSERTM(output_grads.dim() == 4, "expected 3D tensor");
+  AT_ASSERTM(softmax_results.dim() == 4, "expected 3D tensor");
+
+  AT_ASSERTM((output_grads.scalar_type() == at::ScalarType::Half) ||
+	     (output_grads.scalar_type() == at::ScalarType::BFloat16), 
+      "Only fp16 and bf16 are supported");
+  AT_ASSERTM((softmax_results.scalar_type() == at::ScalarType::Half) ||
+	     (softmax_results.scalar_type() == at::ScalarType::BFloat16), 
+      "Only fp16 and bf16 are supported");
+
+  return bwd_cuda(output_grads, softmax_results, scale_factor);
+}
+
+} // end namespace scaled_softmax
+} // end namespace fused_softmax
+} // end namespace multihead_attn
+
+PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
+  m.def("forward", 
+        &multihead_attn::fused_softmax::scaled_softmax::fwd, 
+	"Self Multihead Attention scaled, softmax -- Forward.");
+  m.def("backward", 
+        &multihead_attn::fused_softmax::scaled_softmax::bwd,
+	"Self Multihead Attention scaled, softmax -- Backward.");
+}
+

megatron/fused_kernels/scaled_softmax_cuda.cu

+/* coding=utf-8
+ * Copyright (c) 2020, 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.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <ATen/ATen.h>
+#include <cuda.h>
+#include <cuda_runtime.h>
+#include <cuda_fp16.h>
+#include <cuda_profiler_api.h>
+#include <ATen/cuda/CUDAContext.h>
+#include <torch/extension.h>
+#include "scaled_masked_softmax.h"
+#include "type_shim.h"
+
+namespace multihead_attn {
+namespace fused_softmax {
+namespace scaled_softmax {
+
+torch::Tensor fwd_cuda(
+    torch::Tensor const& input,
+    float scale_factor)
+{
+  // input is a 4d tensor with dimensions [batches, attn_heads, seq_len, seq_len]
+  const int batches = input.size(0);
+  const int attn_heads = input.size(1);
+  const int query_seq_len = input.size(2);
+  const int key_seq_len = input.size(3);
+  TORCH_INTERNAL_ASSERT(key_seq_len <= 4096);
+  TORCH_INTERNAL_ASSERT(query_seq_len > 1);
+
+  // Output 
+  auto act_options = input.options().requires_grad(false);
+  torch::Tensor softmax_results = 
+      torch::empty({batches, attn_heads, query_seq_len, key_seq_len}, act_options);
+
+  // Softmax Intermediate Result Ptr
+  void* input_ptr = static_cast<void*>(input.data_ptr());
+  void* softmax_results_ptr = static_cast<void*>(softmax_results.data_ptr());
+
+  DISPATCH_HALF_AND_BFLOAT(
+      input.scalar_type(),
+      "dispatch_scaled_softmax_forward",
+      dispatch_scaled_softmax_forward<scalar_t, scalar_t, float>(
+          reinterpret_cast<scalar_t*>(softmax_results_ptr),
+	  reinterpret_cast<const scalar_t*>(input_ptr),
+	  scale_factor,
+	  query_seq_len,
+	  key_seq_len,
+	  batches,
+	  attn_heads);
+      );
+  return softmax_results;
+}
+
+torch::Tensor bwd_cuda(
+    torch::Tensor const& output_grads_, 
+    torch::Tensor const& softmax_results_, 
+    float scale_factor)  {
+	
+  auto output_grads = output_grads_.contiguous();
+  auto softmax_results = softmax_results_.contiguous();
+
+  //output grads is a 4d tensor with dimensions [batches, attn_heads, seq_len, seq_len]
+  const int batches = output_grads.size(0);
+  const int attn_heads = output_grads.size(1);
+  const int query_seq_len = output_grads.size(2);
+  const int key_seq_len = output_grads.size(3);
+
+  void* output_grads_ptr = static_cast<void*>(output_grads.data_ptr());
+
+  //Softmax Grad
+  DISPATCH_HALF_AND_BFLOAT(
+      output_grads_.scalar_type(),
+      "dispatch_scaled_masked_softmax_backward",
+      dispatch_scaled_masked_softmax_backward<scalar_t, scalar_t, float>(
+          reinterpret_cast<scalar_t*>(output_grads_ptr), 
+	  reinterpret_cast<scalar_t*>(output_grads_ptr), 
+	  reinterpret_cast<scalar_t const*>(softmax_results.data_ptr()),
+	  scale_factor,
+	  query_seq_len,
+	  key_seq_len,
+	  batches,
+	  attn_heads);
+			   );
+  
+  //backward pass is completely in-place
+  return output_grads;
+}
+}
+}
+}
+

megatron/initialize.py

@@ -62,7 +62,7 @@ def initialize_megatron(extra_args_provider=None, args_defaults={},
         # Random seeds for reproducibility.
         if args.rank == 0:
             print('> setting random seeds to {} ...'.format(args.seed))
-        _set_random_seed(args.seed)
+        _set_random_seed(args.seed, args.data_parallel_random_init)
 
     # Set pytorch JIT layer fusion options.
     _set_jit_fusion_options()
@@ -118,7 +118,7 @@ def _compile_dependencies():
         args.micro_batch_size
     # Constraints on sequence length and attn_batch_size to enable warp based
     # optimization and upper triangular optimization (for causal mask)
-    custom_kernel_constraint = seq_len > 16 and seq_len <=2048 and \
+    custom_kernel_constraint = seq_len > 16 and seq_len <=4096 and \
         seq_len % 4 == 0 and attn_batch_size % 4 == 0
     # Print a warning.
     if not ((args.fp16 or args.bf16) and
@@ -203,11 +203,14 @@ def _init_autoresume():
         torch.distributed.barrier()
 
 
-def _set_random_seed(seed_):
+def _set_random_seed(seed_, data_parallel_random_init=False):
     """Set random seed for reproducability."""
     if seed_ is not None and seed_ > 0:
         # Ensure that different pipeline MP stages get different seeds.
         seed = seed_ + (100 * mpu.get_pipeline_model_parallel_rank())
+        # Ensure different data parallel ranks get different seeds
+        if data_parallel_random_init:
+            seed = seed + (10 * mpu.get_data_parallel_rank())
         random.seed(seed)
         np.random.seed(seed)
         torch.manual_seed(seed)

megatron/model/distributed.py

@@ -185,6 +185,13 @@ class DistributedDataParallel(DistributedDataParallelBase):
             buffer_.zero()
 
 
+    def broadcast_params(self):
+        for param in self.module.parameters():
+            torch.distributed.broadcast(param.data,
+                                        src=mpu.get_data_parallel_src_rank(),
+                                        group=mpu.get_data_parallel_group())
+
+
     def allreduce_gradients(self):
         """Reduce gradients across data parallel ranks."""
         # If we have buffers, simply reduce the data in the buffer.

megatron/model/fused_softmax.py

@@ -81,6 +81,37 @@ class ScaledMaskedSoftmax(torch.autograd.Function):
         return input_grads, None, None
 
 
+class ScaledSoftmax(torch.autograd.Function):
+    """
+    Fused operation which performs following two operations in sequence
+    1. Scale the tensor.
+    2. Perform softmax.
+    """
+
+    @staticmethod
+    def forward(ctx, inputs, scale):
+        import scaled_softmax_cuda
+
+        scale_t = torch.tensor([scale])
+
+        softmax_results = scaled_softmax_cuda.forward(
+            inputs, scale_t[0]
+        )
+        ctx.save_for_backward(softmax_results, scale_t)
+        return softmax_results
+
+    @staticmethod
+    def backward(ctx, output_grads):
+        import scaled_softmax_cuda
+
+        softmax_results, scale_t = ctx.saved_tensors
+
+        input_grads = scaled_softmax_cuda.backward(
+            output_grads, softmax_results, scale_t[0]
+        )
+        return input_grads, None, None
+
+
 class FusedScaleMaskSoftmax(nn.Module):
     """
     fused operation: scaling + mask + softmax
@@ -137,12 +168,11 @@ class FusedScaleMaskSoftmax(nn.Module):
         if (
             self.scaled_masked_softmax_fusion  # user want to fuse
             and self.input_in_float16  # input must be fp16
-            and mask is not None  # mask tensor must not be None
-            and 16 < sk <= 2048  # sk must be 16 ~ 2048
+            and 16 < sk <= 4096  # sk must be 16 ~ 2048
             and sq % 4 == 0  # sq must be divisor of 4
             and attn_batches % 4 == 0  # np * b must be divisor of 4
         ):
-            if 0 <= sk <= 2048:
+            if 0 <= sk <= 4096:
                 batch_per_block = self.get_batch_per_block(sq, sk, b, np)
 
                 if self.attn_mask_type == AttnMaskType.causal:
@@ -166,7 +196,10 @@ class FusedScaleMaskSoftmax(nn.Module):
             return probs.view(b, np, sq, sk)
         else:
             # input is 4D tensor (b, np, sq, sk)
-            return ScaledMaskedSoftmax.apply(input, mask, scale)
+            if mask is not None:
+                return ScaledMaskedSoftmax.apply(input, mask, scale)
+            else:
+                return ScaledSoftmax.apply(input, scale)
 
     def forward_torch_softmax(self, input, mask):
         if self.input_in_float16 and self.softmax_in_fp32:

megatron/model/vision/classification.py

+# coding=utf-8
+# Copyright (c) 2020, 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.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Vision Transformer(VIT) model."""
+
+import torch
+from megatron import get_args
+from megatron.model.utils import get_linear_layer
+from megatron.model.vision.vit_backbone import VitBackbone, VitMlpHead
+from megatron.model.module import MegatronModule
+
+class VitClassificationModel(MegatronModule):
+    """Vision Transformer Model."""
+
+    def __init__(self, num_classes, finetune=False,
+                 pre_process=True, post_process=True):
+        super(VitClassificationModel, self).__init__()
+        args = get_args()
+
+        self.hidden_size = args.hidden_size
+        self.num_classes = num_classes
+        self.finetune = finetune
+        self.pre_process = pre_process
+        self.post_process = post_process
+        self.backbone = VitBackbone(
+            pre_process=self.pre_process,
+            post_process=self.post_process,
+            single_token_output=True
+        )
+        
+        if self.post_process:
+            if not self.finetune:
+                self.head = VitMlpHead(self.hidden_size, self.num_classes)
+            else:
+                self.head = get_linear_layer(
+                    self.hidden_size,
+                    self.num_classes,
+                    torch.nn.init.zeros_
+                )
+
+    def set_input_tensor(self, input_tensor):
+        """See megatron.model.transformer.set_input_tensor()"""
+        self.backbone.set_input_tensor(input_tensor)
+
+    def forward(self, input):
+        hidden_states = self.backbone(input)
+
+        if self.post_process:
+            hidden_states = self.head(hidden_states)
+
+        return hidden_states

megatron/model/vit_model.py → megatron/model/vision/vit_backbone.py

@@ -18,16 +18,19 @@
 import math
 import einops
 import torch
+import apex
 import torch.nn.functional as F
 from megatron import get_args
+from megatron.model import LayerNorm
 from megatron.model.transformer import ParallelTransformer
 from megatron.model.utils import (
     get_linear_layer,
     init_method_normal,
     scaled_init_method_normal,
 )
-from .module import MegatronModule
+from megatron.model.module import MegatronModule
 
+CLASS_TOKEN_LENGTH = 8
 
 class VitMlpHead(MegatronModule):
     """Pooler layer.
@@ -44,19 +47,26 @@ class VitMlpHead(MegatronModule):
     def __init__(self, hidden_size, num_classes):
         super(VitMlpHead, self).__init__()
         self.dense_in = torch.nn.Linear(hidden_size, hidden_size)
+        self.relu = torch.nn.ReLU()
         self.dense_out = torch.nn.Linear(hidden_size, num_classes)
         torch.nn.init.constant_(self.dense_out.bias, -10)
 
-    def forward(self, hidden_states, sequence_index=0):
-        # hidden_states: [b, s, h]
+    def forward(self, hidden_states):
+        # hidden_states: [b, 1, h]
         # sequence_index: index of the token to pool.
-        hidden_state = hidden_states[:, sequence_index, :]
-        dense_in_result = self.dense_in(hidden_state)
+        dense_in_result = self.dense_in(hidden_states)
         tanh_result = torch.tanh(dense_in_result)
         dense_out_result = self.dense_out(tanh_result)
         return dense_out_result
 
 
+def isPerfectSquare(x):
+    if(x >= 0):
+        sr = math.sqrt(x)
+        return (int(sr) * int(sr) == x)
+    return False
+
+
 def twod_interpolate_position_embeddings_hook(
     state_dict,
     prefix,
@@ -68,66 +78,77 @@ def twod_interpolate_position_embeddings_hook(
 ):
 
     args = get_args()
-    num_patches_per_dim = args.img_dim // args.patch_dim
-    num_patches = num_patches_per_dim ** 2
-    seq_length = num_patches + 1
+    num_patches_per_dim_h = args.img_h // args.patch_dim
+    num_patches_per_dim_w = args.img_w // args.patch_dim
+    num_patches = num_patches_per_dim_h * num_patches_per_dim_w
     hidden_size = args.hidden_size
 
     key = prefix + "weight"
-    # import pdb
-    # pdb.set_trace()
+
     assert key in state_dict
     if key in state_dict:
         input_param = state_dict[key]
 
+        input_seq_len = input_param.shape[0]
+        assert(isPerfectSquare(input_seq_len) or isPerfectSquare(input_seq_len - CLASS_TOKEN_LENGTH))
+        input_has_class_token = not isPerfectSquare(input_seq_len)
+        num_tok_input = input_seq_len - CLASS_TOKEN_LENGTH if input_has_class_token else input_seq_len
+        num_tok_output = num_patches
+        output_has_class_token = args.class_token_present
+
+        # update input_param and load it to state_dict[key]
+        if input_has_class_token:
+            input_param_tok = input_param[:CLASS_TOKEN_LENGTH, :]
+            input_param_grid = input_param[CLASS_TOKEN_LENGTH:, :]
+        else:
+            input_param_tok = torch.zeros(CLASS_TOKEN_LENGTH, hidden_size)
+            input_param_grid = input_param
+
         assert input_param.shape[1] == hidden_size
-        if input_param.shape[0] != seq_length:
-            # update input_param and load it to state_dict[key]
-
-            num_tok_input = input_param.shape[0] - 1
-            num_tok_new = seq_length - 1
-            input_param_tok, input_param_grid = (
-                input_param[:1, :],
-                input_param[1:, :],
-            )
+
+        if num_tok_input != num_tok_output:
 
             gs_input = int(math.sqrt(num_tok_input))
-            gs_new = int(math.sqrt(num_tok_new))
+            gs_new = (num_patches_per_dim_h, num_patches_per_dim_w)
 
             input_param_grid = input_param_grid.transpose(0, 1).contiguous()
             input_param_grid = input_param_grid.reshape(
                 (1, -1, gs_input, gs_input)
             )
             input_param_grid = input_param_grid.float()
-            scale_factor = gs_new / gs_input
+            scale_factor = (gs_new[0] / gs_input, gs_new[1] / gs_input)
 
             input_param_grid = F.interpolate(
                 input_param_grid, scale_factor=scale_factor, mode="bilinear"
             )
 
             input_param_grid = input_param_grid.half()
-            input_param_grid = input_param_grid.reshape((-1, gs_new * gs_new))
+            input_param_grid = input_param_grid.reshape((-1, num_tok_output))
             input_param_grid = input_param_grid.transpose(0, 1).contiguous()
 
             assert input_param_grid.shape[1] == hidden_size
-            input_param = torch.cat((input_param_tok, input_param_grid), dim=0)
-            assert (
-                input_param.shape[0] == seq_length
-                and input_param.shape[1] == hidden_size
-            )
 
-            state_dict[key] = input_param
+        input_param = input_param_grid
+        assert (
+            input_param.shape[0] == num_tok_output
+            and input_param.shape[1] == hidden_size
+        )
+
+        if output_has_class_token:
+            input_param = torch.cat((input_param_tok, input_param), dim=0)
+
+        state_dict[key] = input_param
 
 
-class VitModel(MegatronModule):
+class VitBackbone(MegatronModule):
     """Vision Transformer Model."""
 
-    def __init__(self, 
-                 num_classes,
-                 finetune=False,
+    def __init__(self,
                  pre_process=True,
-                 post_process=True):
-        super(VitModel, self).__init__(share_word_embeddings=False)
+                 post_process=True,
+                 class_token=True,
+                 single_token_output=False):
+        super(VitBackbone, self).__init__(share_word_embeddings=False)
         args = get_args()
 
         self.fp16_lm_cross_entropy = args.fp16_lm_cross_entropy
@@ -142,25 +163,33 @@ class VitModel(MegatronModule):
 
         self.pre_process = pre_process
         self.post_process = post_process
+        self.class_token = class_token
         self.hidden_size = args.hidden_size
-        self.num_classes = num_classes
         self.patch_dim = args.patch_dim
-        self.img_dim = args.img_dim
-        self.finetune = finetune
-
-        assert self.img_dim % self.patch_dim == 0
-        self.num_patches_per_dim = self.img_dim // self.patch_dim
-        self.num_patches = self.num_patches_per_dim ** 2
-        self.seq_length = self.num_patches + 1
+        self.img_h = args.img_h
+        self.img_w = args.img_w
+        self.micro_batch_size = args.micro_batch_size
+        self.single_token_output = single_token_output
+
+        assert self.img_h % self.patch_dim == 0
+        assert self.img_w % self.patch_dim == 0
+        self.num_patches_per_dim_h = self.img_h // self.patch_dim
+        self.num_patches_per_dim_w = self.img_w // self.patch_dim
+        self.num_patches = self.num_patches_per_dim_h * self.num_patches_per_dim_w
+        self.seq_length = self.num_patches + (CLASS_TOKEN_LENGTH if self.class_token else 0)
         self.flatten_dim = self.patch_dim * self.patch_dim * args.num_channels
+        self.input_tensor = None
+        self.position_ids = None
 
         if self.pre_process:
             # cls_token
-            self.cls_token = torch.nn.Parameter(
-                torch.randn(1, 1, self.hidden_size)
-            )
-            torch.nn.init.zeros_(self.cls_token)
-
+            if self.class_token:
+                self.cls_token = torch.nn.Parameter(
+                    torch.randn(1, CLASS_TOKEN_LENGTH, self.hidden_size)
+                )
+                torch.nn.init.zeros_(self.cls_token)
+            self.position_ids = torch.arange(self.seq_length).expand(1, -1).cuda()
+            
             # Linear encoder
             self.linear_encoder = torch.nn.Linear(
                 self.flatten_dim, self.hidden_size
@@ -173,8 +202,8 @@ class VitModel(MegatronModule):
             init_method_normal(args.init_method_std)(
                 self.position_embeddings.weight
             )
-            self.position_ids = torch.arange(self.seq_length).expand(1, -1).cuda()
 
+            args.class_token_present = self.class_token
             self.position_embeddings._register_load_state_dict_pre_hook(
                 twod_interpolate_position_embeddings_hook
             )
@@ -183,21 +212,12 @@ class VitModel(MegatronModule):
 
         # Transformer
         self.transformer = ParallelTransformer(
-            self.init_method, 
+            self.init_method,
             self.scaled_init_method,
             pre_process=self.pre_process,
-            post_process=self.post_process
+            post_process=self.post_process,
         )
 
-        if self.post_process:
-            # MLP head
-            if not self.finetune:
-                self.mlp_head = VitMlpHead(self.hidden_size, self.num_classes)
-            else:
-                self.class_head = get_linear_layer(
-                    self.hidden_size, num_classes, torch.nn.init.zeros_
-                )
-
     def set_input_tensor(self, input_tensor):
         """See megatron.model.transformer.set_input_tensor()"""
         self.transformer.set_input_tensor(input_tensor)
@@ -214,21 +234,22 @@ class VitModel(MegatronModule):
 
             assert rearranged_input.dtype == torch.half
             encoder_output = self.linear_encoder(rearranged_input)
-            cls_tokens = self.cls_token.expand(encoder_output.shape[0], -1, -1)
-            concatenated_tokens = torch.cat((cls_tokens, encoder_output), dim=1)
+
+            concatenated_tokens = encoder_output
+            if self.class_token:
+                cls_tokens = self.cls_token.expand(encoder_output.shape[0], -1, -1)
+                concatenated_tokens = torch.cat((cls_tokens, encoder_output), dim=1)
 
             token_embeddings = concatenated_tokens + \
-                self.position_embeddings(self.position_ids)
+                    self.position_embeddings(self.position_ids[:, :concatenated_tokens.shape[1]])
             hidden_states = self.embedding_dropout(token_embeddings)
         else:
             hidden_states = input
 
         hidden_states = self.transformer(hidden_states, None)
 
-        if self.post_process:
-            if not self.finetune:
-                hidden_states = self.mlp_head(hidden_states)
-            else:
-                hidden_states = self.class_head(hidden_states[:, 0, :])
+        if self.single_token_output:
+            hidden_states = hidden_states[:,0,:]
 
         return hidden_states
+

megatron/mpu/__init__.py

@@ -38,6 +38,7 @@ from .initialize import is_pipeline_stage_before_split, is_pipeline_stage_after_
 from .initialize import is_pipeline_stage_at_split
 from .initialize import get_num_layers
 from .initialize import get_tensor_model_parallel_src_rank
+from .initialize import get_data_parallel_src_rank
 from .initialize import get_pipeline_model_parallel_first_rank
 from .initialize import get_pipeline_model_parallel_last_rank
 from .initialize import get_pipeline_model_parallel_next_rank

megatron/mpu/initialize.py

@@ -452,6 +452,15 @@ def get_tensor_model_parallel_src_rank():
     return (global_rank // local_world_size) * local_world_size
 
 
+def get_data_parallel_src_rank():
+    """Calculate the global rank corresponding to the first local rank
+    in the tensor model parallel group."""
+    global_rank = torch.distributed.get_rank()
+    data_parallel_size = get_data_parallel_world_size()
+    num_data_parallel_groups = torch.distributed.get_world_size() // data_parallel_size
+    return global_rank % num_data_parallel_groups
+
+
 def get_pipeline_model_parallel_first_rank():
     assert _PIPELINE_GLOBAL_RANKS is not None, \
         "Pipeline parallel group is not initialized"

megatron/optimizer/__init__.py

@@ -35,14 +35,14 @@ def _get_params_for_weight_decay_optimization(modules):
             if isinstance(module_, LayerNorm):
                 no_weight_decay_params['params'].extend(
                     [p for p in list(module_._parameters.values())
-                     if p is not None])
+                     if p is not None and p.requires_grad])
             else:
                 weight_decay_params['params'].extend(
                     [p for n, p in list(module_._parameters.items())
-                     if p is not None and n != 'bias'])
+                     if p is not None and p.requires_grad and n != 'bias'])
                 no_weight_decay_params['params'].extend(
                     [p for n, p in list(module_._parameters.items())
-                     if p is not None and n == 'bias'])
+                     if p is not None and p.requires_grad and n == 'bias'])
 
     return weight_decay_params, no_weight_decay_params
 

megatron/training.py

@@ -285,7 +285,10 @@ def get_model(model_provider_func, model_type=ModelType.encoder_or_decoder, wrap
                               args.accumulate_allreduce_grads_in_fp32,
                               args.use_contiguous_buffers_in_local_ddp)
                      for model_module in model]
-
+            # broad cast params from data parallel src rank to other data parallel ranks
+            if args.data_parallel_random_init:
+                for model_module in model:
+                    model_module.broadcast_params()
         else:
             raise NotImplementedError('Unknown DDP implementation specified: '
                                       '{}. Exiting.'.format(args.DDP_impl))

pretrain_vit.py

@@ -21,7 +21,7 @@ from functools import partial
 from megatron import get_args, get_timers, mpu, print_rank_0
 from megatron.data.vit_dataset import build_train_valid_datasets
 from megatron.model import ModelType
-from megatron.model.vit_model import VitModel
+from megatron.model.vision.classification import VitClassificationModel
 from megatron.training import pretrain
 from megatron.utils import average_losses_across_data_parallel_group
 
@@ -31,9 +31,9 @@ def model_provider(pre_process=True, post_process=True):
     print_rank_0("building VIT model ...")
     args = get_args()
 
-    model = VitModel(num_classes=args.num_classes,
-                     pre_process=pre_process,
-                     post_process=post_process)
+    model = VitClassificationModel(num_classes=args.num_classes,
+                                   pre_process=pre_process,
+                                   post_process=post_process)
     return model
 
 def get_batch(data_iterator):
@@ -82,7 +82,10 @@ def train_valid_test_datasets_provider(train_val_test_num_samples):
     print_rank_0(
         "> building train, validation, and test datasets " "for VIT ..."
     )
-    train_ds, valid_ds = build_train_valid_datasets(data_path=args.data_path)
+    train_ds, valid_ds = build_train_valid_datasets(
+        data_path=args.data_path,
+        image_size=(args.img_h, args.img_w)
+    )
     print_rank_0("> finished creating VIT datasets ...")
 
     return train_ds, valid_ds, None