ConnectionRefusedError: [Errno 111] Connection refused

在网络连接良好的情况下训练网络，训练的时候突然出现ConnectionRefusedError: [Errno 111] Connection refused，而且此时第一个Epoch还没有运行完成！

有可能是训练数据出了问题。比如，如下报错信息：

Traceback (most recent call last):
  File "train.py", line 90, in <module>
    train(opt, data_loader, model, visualizer)
  File "train.py", line 34, in train
    for i, data in enumerate(dataset):
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/utils/data/dataloader.py", line 267, in __next__
    return self._process_next_batch(batch)
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/utils/data/dataloader.py", line 301, in _process_next_batch
    raise batch.exc_type(batch.exc_msg)
OSError: Traceback (most recent call last):
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/utils/data/dataloader.py", line 55, in _worker_loop
    samples = collate_fn([dataset[i] for i in batch_indices])
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/utils/data/dataloader.py", line 55, in <listcomp>
    samples = collate_fn([dataset[i] for i in batch_indices])
  File "/********/DeepLearningLCT/DeblurGAN-master/self_data_multitask_1024/data/aligned_dataset.py", line 31, in __getitem__
    AB = Image.open(AB_path).convert('L')
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/PIL/Image.py", line 2687, in open
    % (filename if filename else fp))
OSError: cannot identify image file './data/data_1024/AB/train/31636_7.png'

Exception ignored in: <bound method DataLoaderIter.__del__ of <torch.utils.data.dataloader.DataLoaderIter object at 0x7fdfd12f43c8>>
Traceback (most recent call last):
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/utils/data/dataloader.py", line 333, in __del__
    self._shutdown_workers()
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/utils/data/dataloader.py", line 319, in _shutdown_workers
    self.data_queue.get()
  File "/********anaconda3/envs/python36/lib/python3.6/multiprocessing/queues.py", line 337, in get
    return _ForkingPickler.loads(res)
  File "/********/anaconda3/envs/python36/lib/python3.6/site-packages/torch/multiprocessing/reductions.py", line 70, in rebuild_storage_fd
    fd = df.detach()
  File "/********/anaconda3/envs/python36/lib/python3.6/multiprocessing/resource_sharer.py", line 57, in detach
    with _resource_sharer.get_connection(self._id) as conn:
  File "/********/anaconda3/envs/python36/lib/python3.6/multiprocessing/resource_sharer.py", line 87, in get_connection
    c = Client(address, authkey=process.current_process().authkey)
  File "/********/anaconda3/envs/python36/lib/python3.6/multiprocessing/connection.py", line 487, in Client
    c = SocketClient(address)
  File "/********/anaconda3/envs/python36/lib/python3.6/multiprocessing/connection.py", line 614, in SocketClient
    s.connect(address)
ConnectionRefusedError: [Errno 111] Connection refused

问题并不出在服务器的网络连接上，而是出在训练集中的 './data/data_1024/AB/train/31636_7.png'上。

例如：

生成该图像的代码错误中止导致该图像无法正常读取。

解决方法：

重新生成训练数据。

成功解决