Train longer, generalize better - Big batch training

This is a code repository used to generate the results appearing in "Train longer, generalize better: closing the generalization gap in large batch training of neural networks" By Elad Hoffer, Itay Hubara and Daniel Soudry.

It is based off convNet.pytorch with some helpful options such as:

  • Training on several datasets
  • Complete logging of trained experiment
  • Graph visualization of the training/validation loss and accuracy
  • Definition of preprocessing and optimization regime for each model



  • Configure your dataset path at
  • To get the ILSVRC data, you should register on their site for access:

Experiment examples

python --dataset cifar10 --model resnet --save cifar10_resnet44_bs2048_lr_fix --epochs 100 --b 2048 --lr_bb_fix;
python --dataset cifar10 --model resnet --save cifar10_resnet44_bs2048_regime_adaptation --epochs 100 --b 2048 --lr_bb_fix --regime_bb_fix;
python --dataset cifar10 --model resnet --save cifar10_resnet44_bs2048_ghost_bn256 --epochs 100 --b 2048 --lr_bb_fix --mini-batch-size 256;
python --dataset cifar100 --model resnet --save cifar100_wresnet16_4_bs1024_regime_adaptation --epochs 100 --b 1024 --lr_bb_fix --regime_bb_fix;
python --model mnist_f1 --dataset mnist --save mnist_baseline_bs4096_gbn --epochs 50 --b 4096 --lr_bb_fix --no-regime_bb_fix --mini-batch-size 128;
  • See for more examples

Model configuration

Network model is defined by writing a .py file in models folder, and selecting it using the model flag. Model function must be registered in models/
The model function must return a trainable network. It can also specify additional training options such optimization regime (either a dictionary or a function), and input transform modifications.

e.g for a model definition:

class Model(nn.Module):

    def __init__(self, num_classes=1000):
        super(Model, self).__init__()
        self.model = nn.Sequential(...)

        self.regime = {
            0: {'optimizer': 'SGD', 'lr': 1e-2,
                'weight_decay': 5e-4, 'momentum': 0.9},
            15: {'lr': 1e-3, 'weight_decay': 0}

        self.input_transform = {
            'train': transforms.Compose([...]),
            'eval': transforms.Compose([...])
    def forward(self, inputs):
        return self.model(inputs)

 def model(**kwargs):
        return Model()