错误代码：

File "D:\Users\Administrator\miniconda3\lib\runpy.py", line 85, in run_code
    exec(code, run_globals)
  File "E:\project\weilan\YOLOv5-Lite-master\train.py", line 12, in <module>
    import torch.distributed as dist
  File "D:\Users\Administrator\miniconda3\lib\site-packages\torch_init.py", line 117, in <module>
    raise err
OSError: [WinError 1455] 页面文件太小，无法完成操作。 Error loading "D:\Users\Administrator\miniconda3\lib\site-packages\torch\lib\caffe2_detectron_ops_gpu.dll" or one of its dependencies.
Traceback (most recent call last):
  File "E:/project/weilan/YOLOv5-Lite-master/train.py", line 544, in <module>
    train(hyp, opt, device, tb_writer)
  File "E:/project/weilan/YOLOv5-Lite-master/train.py", line 203, in train
    pad=0.5, prefix=colorstr('val: '))[0]
  File "E:\project\weilan\YOLOv5-Lite-master\utils\datasets.py", line 142, in create_dataloader
    collate_fn=LoadImagesAndLabels.collate_fn4 if quad else LoadImagesAndLabels.collate_fn)
  File "E:\project\weilan\YOLOv5-Lite-master\utils\datasets.py", line 155, in init
    self.iterator = super().iter()
  File "D:\Users\Administrator\miniconda3\lib\site-packages\torch\utils\data\dataloader.py", line 352, in iter
    return self._get_iterator()
  File "D:\Users\Administrator\miniconda3\lib\site-packages\torch\utils\data\dataloader.py", line 294, in _get_iterator
    return _MultiProcessingDataLoaderIter(self)
  File "D:\Users\Administrator\miniconda3\lib\site-packages\torch\utils\data\dataloader.py", line 801, in init
    w.start()
  File "D:\Users\Administrator\miniconda3\lib\multiprocessing\process.py", line 112, in start
    self._popen = self._Popen(self)
  File "D:\Users\Administrator\miniconda3\lib\multiprocessing\context.py", line 223, in _Popen
    return _default_context.get_context().Process._Popen(process_obj)
  File "D:\Users\Administrator\miniconda3\lib\multiprocessing\context.py", line 322, in _Popen
    return Popen(process_obj)
  File "D:\Users\Administrator\miniconda3\lib\multiprocessing\popen_spawn_win32.py", line 89, in init
    reduction.dump(process_obj, to_child)
  File "D:\Users\Administrator\miniconda3\lib\multiprocessing\reduction.py", line 60, in dump
    ForkingPickler(file, protocol).dump(obj)
BrokenPipeError: [Errno 32] Broken pipe

Process finished with exit code 1
 

原因：多进程加载数据，超过cpu核数了，

解决方法，减小workers，我的改为4可以了。