[FIXED] pytorch save and load model

Issue

Is there any difference between original model and saved then loaded model?

Before training, I just saved model and then loaded because I wanted to know if there is any changes during saving and loading.

Here's my code

just model for test

class test_model(nn.Module):
    def __init__(self):
        super().__init__()

        self.conv1 = nn.Conv2d(in_channels = 3, out_channels = 50, kernel_size = 3, stride=1, padding=1, bias = False)
        self.maxpool1 = nn.MaxPool2d(2, 2)
        self.bn1 = nn.BatchNorm2d(50)
        
        self.conv2_ = nn.Conv2d(in_channels = 50, out_channels = 10, kernel_size = 1, stride=1, padding=0, bias = False)
        self.conv2 = nn.Conv2d(in_channels = 10, out_channels = 50, kernel_size = 3, stride=1, padding=1, bias = False)
        self.maxpool2 = nn.MaxPool2d(2, 2)
        self.bn2 = nn.BatchNorm2d(50)

        self.conv3_ = nn.Conv2d(in_channels = 50, out_channels = 10, kernel_size = 1, stride=1, padding=0, bias = False)
        self.conv3 = nn.Conv2d(in_channels = 10, out_channels = 50, kernel_size = 3, stride=1, padding=1, bias = False)
        self.maxpool3 = nn.MaxPool2d(2, 2)
        self.bn3 = nn.BatchNorm2d(50)
        
        self.conv4_ = nn.Conv2d(in_channels = 50, out_channels = 20, kernel_size = 1, stride=1, padding=0, bias = False)
        self.conv4 = nn.Conv2d(in_channels =20, out_channels = 100, kernel_size = 3, stride=1, padding=1, bias = False)
        self.maxpool4 = nn.MaxPool2d(2, 2)
        self.bn4 = nn.BatchNorm2d(100)

        self.conv5_ = nn.Conv2d(in_channels = 100, out_channels = 10, kernel_size = 1, stride=1, padding=0, bias = False)
        self.conv5 = nn.Conv2d(in_channels = 10, out_channels = 100, kernel_size = 3, stride=1, padding=1, bias = False)
        self.maxpool5 = nn.MaxPool2d(2, 2)
        self.bn5 = nn.BatchNorm2d(100)
        
        self.fc = nn.Sequential(Flatten(),
                               nn.Linear(100*7*7, 100),
                                nn.ReLU(),
                               nn.Linear(100,100))
        
    def forward(self, inputs):
        feature_map1 = self.conv1(inputs)
        feature_map1 = self.maxpool1(feature_map1)
        feature_map1 = self.bn1(feature_map1)
        
        feature_map2 = self.conv2_(feature_map1)
        feature_map2 = self.conv2(feature_map2)
        feature_map2 = self.maxpool2(feature_map2)
        feature_map2 = self.bn2(feature_map2)
         
        feature_map3 = self.conv3_(feature_map2)   
        feature_map3 = self.conv3(feature_map3)
        feature_map3 = self.maxpool3(feature_map3)
        feature_map3 = self.bn3(feature_map3)
        
        feature_map4 = self.conv4_(feature_map3)
        feature_map4 = self.conv4(feature_map4)
        feature_map4 = self.maxpool4(feature_map4)
        feature_map4 = self.bn4(feature_map4)
        
        feature_map5 = self.conv5_(feature_map4)
        feature_map5 = self.conv5(feature_map5)
        feature_map5 = self.maxpool5(feature_map5)
        feature_map5 = self.bn5(feature_map5)
           
        output = self.fc(feature_map5)
        
        return output

then

model_cpu = test_model()

save and load

torch.save(model_cpu, '/home/mskang/hyeokjong/model_cpu.pt')
model_load = torch.load('/home/mskang/hyeokjong/model_cpu.pt')

and

model_load  == model_cpu
------------------------------------
False

However

print(model_load)
print(model_cpu)

are seemed same

furthermore

I also trained two models(model_load, model_cpu) and results looks same too.

So I think those tow models are same and should be same But why False

Solution

They have the same underlying model but are different Python objects. That is why __eq__ returns False when trying model_load == model_cpu. You can see model_load and model_cpu as two copies of the same nn.Module.

Answered By - Ivan