KD-pytorch

• Knowledge Distillation (KD) - pytorch
• PyTorch implementation of Distilling the Knowledge in a Neural Network
• This repository is forked from pytorch-cifar.
• Dataset: CIFAR10
• Teacher Network: VGG16
• Student Network: CNN with 3 convolutional blocks

Prerequisites

• Python 3.6+
• PyTorch 1.0+
• See docker/ folder.

Pretrain Teacher Networks

• Result: 91.90%
• SGD, no weight decay.
• Learning rate adjustment
  • 0.1 for epoch [1,150]
  • 0.01 for epoch [151,250]
  • 0.001 for epoch [251,300]

python -m pretrainer --optimizer=sgd --lr=0.1   --start_epoch=1   --n_epoch=150 --model_name=ckpt
python -m pretrainer --optimizer=sgd --lr=0.01  --start_epoch=151 --n_epoch=100 --model_name=ckpt --resume
python -m pretrainer --optimizer=sgd --lr=0.001 --start_epoch=251 --n_epoch=50  --model_name=ckpt --resume

Student Networks

• We use Adam optimizer for fair comparison.
  • max epoch: 300
  • learning rate: 0.0001
  • no weight decay for fair comparison.

EXP0. Baseline (without Knowledge Distillation)

• Result: 85.01%

python -m pretrainer --optimizer=adam --lr=0.0001 --start_epoch=1 --n_epoch=300 --model_name=student-scratch --network=studentnet

EXP1. Effect of loss function

• Similar performance.

python -m trainer --T=1.0 --alpha=1.0 --kd_mode=cse # 84.99%
python -m trainer --T=1.0 --alpha=1.0 --kd_mode=mse # 84.85%

EXP2. Effect of Alpha

• alpha = 0.5 may show better performance.

python -m trainer --T=1.0 --alpha=1.0 --kd_mode=cse # 84.99%
python -m trainer --T=1.0 --alpha=0.5 --kd_mode=cse # 85.38%
python -m trainer --T=1.0 --alpha=1.0 --kd_mode=mse # 84.85%
python -m trainer --T=1.0 --alpha=0.5 --kd_mode=mse # 84.92%

EXP3. Effect of Temperature Scaling

• Higher the temperature, better the performance. Consistent results with the paper.

python -m trainer --T=1.0  --alpha=0.5 --kd_mode=cse # 85.38%
python -m trainer --T=2.0  --alpha=0.5 --kd_mode=cse # 85.27%
python -m trainer --T=4.0  --alpha=0.5 --kd_mode=cse # 86.46%
python -m trainer --T=8.0  --alpha=0.5 --kd_mode=cse # 86.33%
python -m trainer --T=16.0 --alpha=0.5 --kd_mode=cse # 86.58%

EXP4. More Alpha Tuning

• alpha=0.5 seems to be local optimal.

python -m trainer --T=16.0 --alpha=0.1 --kd_mode=cse # 85.69%
python -m trainer --T=16.0 --alpha=0.3 --kd_mode=cse # 86.48%
python -m trainer --T=16.0 --alpha=0.5 --kd_mode=cse # 86.58%
python -m trainer --T=16.0 --alpha=0.7 --kd_mode=cse # 86.16%
python -m trainer --T=16.0 --alpha=0.9 --kd_mode=cse # 86.08%

EXP5. SGD Testing

python -m trainer --T=16.0 --alpha=0.5 --kd_mode=cse --optimizer=sgd-cifar10 # 87.04%
python -m pretrainer --model_name=student-scratch-sgd-cifar10 --network=studentnet --optimizer=sgd-cifar10 # 86.34%

TODO

• fix seed.
• multi gpu handling.
• split validation set.
• experiments with 5 random seed.
• remove code redundancy.
• check the optimal T is equal to calibrated T.
• Progressbar code fix in trainer.py.