TORCH.UTILS.BOTTLENECK介绍

`torch.utils.bottleneck`是PyTorch中的一个性能优化工具，旨在帮助用户找到代码中的瓶颈并提高代码的运行速度。它提供了一组函数和类，可以在Python解释器中运行代码，并提供有关函数调用时间和内存分配情况的详细信息。对于大型数据集和复杂模型，使用该工具可以显著减少训练和推理时间。使用`bottleneck`时，用户需要将代码包装在一个`with torch.autograd.profiler.profile():`语句块中，以便记录函数调用时间和内存使用情况。同时，`bottleneck`还提供了一些其他的工具，如`optimize_for_inference`函数，可以优化模型以便在推理过程中更快地运行。

相关问题

AttributeError: module 'torch.nn.modules' has no attribute 'resnet50'

这个错误通常是由于PyTorch版本问题引起的。在较旧的版本中，`resnet50`是在`torchvision.models`中定义的，而在较新的版本中，它被移动到了`torchvision.models.resnet`中。因此，如果您使用的是较旧的版本，请使用以下代码：

import torchvision.models as models

resnet50 = models.resnet50(pretrained=True)

如果您使用的是较新的版本，请使用以下代码：

import torch.nn as nn
import torch.utils.model_zoo as model_zoo

model_urls = {
    'resnet18': 'https://download.pytorch.org/models/resnet18-5c106cde.pth',
    'resnet34': 'https://download.pytorch.org/models/resnet34-333f7ec4.pth',
    'resnet50': 'https://download.pytorch.org/models/resnet50-19c8e357.pth',
    'resnet101': 'https://download.pytorch.org/models/resnet101-5d3b4d8f.pth',
    'resnet152': 'https://download.pytorch.org/models/resnet152-b121ed2d.pth',
}

class ResNet(nn.Module):

    def __init__(self, block, layers, num_classes=1000):
        self.inplanes = 64
        super(ResNet, self).__init__()
        self.conv1 = nn.Conv2d(3, 64, kernel_size=7, stride=2, padding=3,
                               bias=False)
        self.bn1 = nn.BatchNorm2d(64)
        self.relu = nn.ReLU(inplace=True)
        self.maxpool = nn.MaxPool2d(kernel_size=3, stride=2, padding=1)
        self.layer1 = self._make_layer(block, 64, layers[0])
        self.layer2 = self._make_layer(block, 128, layers[1], stride=2)
        self.layer3 = self._make_layer(block, 256, layers[2], stride=2)
        self.layer4 = self._make_layer(block, 512, layers[3], stride=2)
        self.avgpool = nn.AdaptiveAvgPool2d((1, 1))
        self.fc = nn.Linear(512 * block.expansion, num_classes)

        for m in self.modules():
            if isinstance(m, nn.Conv2d):
                nn.init.kaiming_normal_(m.weight, mode='fan_out', nonlinearity='relu')
            elif isinstance(m, (nn.BatchNorm2d, nn.GroupNorm)):
                nn.init.constant_(m.weight, 1)
                nn.init.constant_(m.bias, 0)

        for m in self.modules():
            if isinstance(m, Bottleneck):
                nn.init.constant_(m.bn3.weight, 0)

    def _make_layer(self, block, planes, blocks, stride=1):
        downsample = None
        if stride != 1 or self.inplanes != planes * block.expansion:
            downsample = nn.Sequential(
                nn.Conv2d(self.inplanes, planes * block.expansion,
                          kernel_size=1, stride=stride, bias=False),
                nn.BatchNorm2d(planes * block.expansion),
            )

        layers = []
        layers.append(block(self.inplanes, planes, stride, downsample))
        self.inplanes = planes * block.expansion
        for _ in range(1, blocks):
            layers.append(block(self.inplanes, planes))

        return nn.Sequential(*layers)

    def forward(self, x):
        x = self.conv1(x)
        x = self.bn1(x)
        x = self.relu(x)
        x = self.maxpool(x)

        x = self.layer1(x)
        x = self.layer2(x)
        x = self.layer3(x)
        x = self.layer4(x)

        x = self.avgpool(x)
        x = x.view(x.size(0), -1)
        x = self.fc(x)

        return x

def resnet50(pretrained=False, **kwargs):
    model = ResNet(Bottleneck, [3, 4, 6, 3], **kwargs)
    if pretrained:
        state_dict = model_zoo.load_url(model_urls['resnet50'])
        model.load_state_dict(state_dict)
    return model

resnet50 = resnet50(pretrained=True)

Traceback (most recent call last): File "train.py", line 354, in <module> fit_one_epoch(model_train, model, yolo_loss, loss_history, optimizer, epoch, epoch_step, epoch_step_val, gen, gen_val, UnFreeze_Epoch, Cuda, save_period, save_dir) File "/hy-tmp/yolov5-pytorch-bilibili/yolov5-pytorch-bilibili/utils/utils_fit.py", line 34, in fit_one_epoch outputs = model_train(images) File "/usr/local/miniconda3/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1194, in _call_impl return forward_call(*input, **kwargs) File "/usr/local/miniconda3/lib/python3.8/site-packages/torch/nn/parallel/data_parallel.py", line 169, in forward return self.module(*inputs[0], **kwargs[0]) File "/usr/local/miniconda3/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1194, in _call_impl return forward_call(*input, **kwargs) File "/hy-tmp/yolov5-pytorch-bilibili/yolov5-pytorch-bilibili/nets/yolo.py", line 102, in forward self.h3 = self.bottlenecklstm3(P3, self.h3, self.c3) # lstm File "/usr/local/miniconda3/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1194, in _call_impl return forward_call(*input, **kwargs) File "/hy-tmp/yolov5-pytorch-bilibili/yolov5-pytorch-bilibili/nets/bottleneck_lstm.py", line 141, in forward new_h, new_c = self.cell(inputs, h, c) File "/usr/local/miniconda3/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1194, in _call_impl return forward_call(*input, **kwargs) File "/hy-tmp/yolov5-pytorch-bilibili/yolov5-pytorch-bilibili/nets/bottleneck_lstm.py", line 68, in forward y = torch.cat((x, h),1) RuntimeError: Expected all tensors to be on the same device, but found at least two devices, cuda:0 and cpu! (when checking argument for argument tensors in method wrapper_cat)

这个错误通常是由于将位于不同设备（如GPU和CPU）上的张量传递给需要所有张量都在同一设备上的函数或方法，例如`torch.cat()`方法。要解决这个问题，需要将所有张量都移动到同一设备上，或者使用支持跨设备的函数（如`torch.nn.DataParallel()`）来处理它们。可以使用`tensor.to(device)`方法将张量移动到指定设备上，其中`device`可以是字符串（如`"cuda:0"`）或`torch.device()`对象。在这个特定的错误中，很可能是将GPU上的张量与CPU上的张量拼接在一起，因此需要将所有张量移动到同一设备上。可以使用`tensor.to(device)`方法将张量移动到指定设备上，其中`device`可以是字符串（如`"cuda:0"`）或`torch.device()`对象。