Pytorch 为什么mobilenet比vgg慢？

我在同一张图片上尝试了vgg16和mobilenet v2预训练模型（输入大小=224）。vgg16的推理时间（6ms）比mobilenet v2（12ms）短。我认为mobilenet应该比vgg快得多。有人对此有想法吗？谢谢这是我的密码

import torch
import cv2
from torchvision import transforms
import time

if __name__ == "__main__":

    model_mobile = torch.hub.load('pytorch/vision:v0.9.0', 'mobilenet_v2', pretrained=True)
    model_mobile.eval()
    model_mobile.cuda()

    model_vgg = torch.hub.load('pytorch/vision:v0.9.0', 'vgg16', pretrained=True)
    model_vgg.eval()
    model_vgg.cuda()

    preprocess = transforms.Compose([
        transforms.ToTensor(),
        transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
    ])
    im = cv2.imread('1.jpg')
    im = preprocess(im)
    im = im.unsqueeze(0)
    im = im.cuda()


    result_mobile = model_mobile(im)


    t1 = time.time()
    result_mobile = model_mobile(im)
    t2 = time.time()
    result_vgg = model_vgg(im)
    t3= time.time()

    print("mobilenet time = {:.3f}".format(t2-t1))
    print("vgg time = {:.3f}".format(t3-t2))