[mcj]RuntimeError: Attempting to deserialize object on a CUDA device but torch.cuda.is_available() is False. If you are running on a CPU-only machine, please use torch.load with map_location=’cpu’ to map your storages to the CPU.

运行pytorch的时候，出现报错：

/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py:454: SourceChangeWarning: source code of class 'model.SSD300' has changed. you can retrieve the original source code by accessing the object's source attribute or set `torch.nn.Module.dump_patches = True` and use the patch tool to revert the changes.
  warnings.warn(msg, SourceChangeWarning)
Traceback (most recent call last):
  File "train.py", line 234, in <module>
    main()
  File "train.py", line 57, in main
    checkpoint = torch.load(checkpoint)
  File "/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py", line 387, in load
    return _load(f, map_location, pickle_module, **pickle_load_args)
  File "/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py", line 574, in _load
    result = unpickler.load()
  File "/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py", line 537, in persistent_load
    deserialized_objects[root_key] = restore_location(obj, location)
  File "/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py", line 119, in default_restore_location
    result = fn(storage, location)
  File "/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py", line 95, in _cuda_deserialize
    device = validate_cuda_device(location)
  File "/usr/local/python3/lib/python3.6/site-packages/torch/serialization.py", line 79, in validate_cuda_device
    raise RuntimeError('Attempting to deserialize object on a CUDA '
RuntimeError: Attempting to deserialize object on a CUDA device but torch.cuda.is_available() is False. If you are running on a CPU-only machine, please use torch.load with map_location='cpu' to map your storages to the CPU.

报错原因：

这种情况一般就是pytorch与cuda版本不一致，先查看pytorch支持的cuda的版本：

>>> import torch
>>> torch.version.cuda
'10.0.130'

然后看一下目前cuda的版本：

nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2017 NVIDIA Corporation
Built on Fri_Nov__3_21:07:56_CDT_2017
Cuda compilation tools, release 9.1, V9.1.85

很明显，不匹配，需要更换cuda版本才可以。