super-gradients/tests/unit_tests/kd_ema_test.py

import unittest

from super_gradients.training import models
from super_gradients.training import Trainer
from super_gradients.training.dataloaders.dataloaders import classification_test_dataloader
from super_gradients.training.kd_trainer import KDTrainer
import torch
from super_gradients.training.utils.utils import check_models_have_same_weights
from super_gradients.training.metrics import Accuracy
from super_gradients.training.losses.kd_losses import KDLogitsLoss


class KDEMATest(unittest.TestCase):
    @classmethod
    def setUp(cls):
        cls.sg_trained_teacher = Trainer("sg_trained_teacher", device='cpu')

        cls.kd_train_params = {"max_epochs": 3, "lr_updates": [1], "lr_decay_factor": 0.1, "lr_mode": "step",
                               "lr_warmup_epochs": 0, "initial_lr": 0.1,
                               "loss": KDLogitsLoss(torch.nn.CrossEntropyLoss()),
                               "optimizer": "SGD",
                               "criterion_params": {}, "optimizer_params": {"weight_decay": 1e-4, "momentum": 0.9},
                               "train_metrics_list": [Accuracy()], "valid_metrics_list": [Accuracy()],
                               "metric_to_watch": "Accuracy",
                               'loss_logging_items_names': ["Loss", "Task Loss", "Distillation Loss"],
                               "greater_metric_to_watch_is_better": True, "average_best_models": False,
                               "ema": True}

    def test_teacher_ema_not_duplicated(self):
        """Check that the teacher EMA is a reference to the teacher net (not a copy)."""

        kd_model = KDTrainer("test_teacher_ema_not_duplicated", device='cpu')
        student = models.get('resnet18', arch_params={'num_classes': 1000})
        teacher = models.get('resnet50', arch_params={'num_classes': 1000},
                             pretrained_weights="imagenet")

        kd_model.train(training_params=self.kd_train_params, student=student, teacher=teacher,
                       train_loader=classification_test_dataloader(),
                       valid_loader=classification_test_dataloader())

        self.assertTrue(kd_model.ema_model.ema.module.teacher is kd_model.net.module.teacher)
        self.assertTrue(kd_model.ema_model.ema.module.student is not kd_model.net.module.student)

    def test_kd_ckpt_reload_net(self):
        """Check that the KD trainer load correctly from checkpoint when "load_ema_as_net=False"."""

        # Create a KD trainer and train it
        train_params = self.kd_train_params.copy()
        kd_model = KDTrainer("test_kd_ema_ckpt_reload", device='cpu')
        student = models.get('resnet18', arch_params={'num_classes': 1000})
        teacher = models.get('resnet50', arch_params={'num_classes': 1000},
                             pretrained_weights="imagenet")

        kd_model.train(training_params=self.kd_train_params, student=student, teacher=teacher,
                       train_loader=classification_test_dataloader(),
                       valid_loader=classification_test_dataloader())
        ema_model = kd_model.ema_model.ema
        net = kd_model.net

        # Load the trained KD trainer
        kd_model = KDTrainer("test_kd_ema_ckpt_reload", device='cpu')
        student = models.get('resnet18', arch_params={'num_classes': 1000})
        teacher = models.get('resnet50', arch_params={'num_classes': 1000},
                             pretrained_weights="imagenet")

        train_params["resume"] = True
        kd_model.train(training_params=train_params, student=student, teacher=teacher,
                       train_loader=classification_test_dataloader(),
                       valid_loader=classification_test_dataloader())
        reloaded_ema_model = kd_model.ema_model.ema
        reloaded_net = kd_model.net

        # trained ema == loaded ema (Should always be true as long as "ema=True" in train_params)
        self.assertTrue(check_models_have_same_weights(ema_model, reloaded_ema_model))

        # loaded net == trained net (since load_ema_as_net = False)
        self.assertTrue(check_models_have_same_weights(reloaded_net, net))

        # loaded net != trained ema (since load_ema_as_net = False)
        self.assertTrue(not check_models_have_same_weights(reloaded_net, ema_model))

        # loaded student ema == loaded  student net (since load_ema_as_net = False)
        self.assertTrue(
            not check_models_have_same_weights(reloaded_ema_model.module.student, reloaded_net.module.student))

        # loaded teacher ema == loaded teacher net (teacher always loads ema)
        self.assertTrue(check_models_have_same_weights(reloaded_ema_model.module.teacher, reloaded_net.module.teacher))


if __name__ == '__main__':
    unittest.main()