BrokenPipeError: [Errno 32] Broken pipe

[Matthew Chen]

When I cloned the repository and ran main.py (without changing anything) I get this output:

 not enough values to unpack (expected 2, got 0)
 ==> Preparing data..
 Files already downloaded and verified
 Files already downloaded and verified
 Training with dataset CIFAR10 and 10 classes 
 ==> Building model..
 ==> Checkpoints will be saved to: ./checkpoint/ckpt-CIFAR10-ResNet18.pth
 classes:	(callable) 

 Epoch: 0
 Traceback (most recent call last):

File "<ipython-input-7-f9bd8031870b>", line 1, in <module>
  runfile('C:/Users/Matthew Chen/Documents/GitHub/neural-backed-decision-trees/main.py', wdir='C:/Users/Matthew Chen/Documents/GitHub/neural-backed-decision-trees')

File "C:\Users\Matthew Chen\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 827, in runfile
  execfile(filename, namespace)

File "C:\Users\Matthew Chen\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 110, in execfile
  exec(compile(f.read(), filename, 'exec'), namespace)

File "C:/Users/Matthew Chen/Documents/GitHub/neural-backed-decision-trees/main.py", line 315, in <module>
  train(epoch, analyzer)

File "C:/Users/Matthew Chen/Documents/GitHub/neural-backed-decision-trees/main.py", line 227, in train
  for batch_idx, (inputs, targets) in enumerate(trainloader):

File "C:\Users\Matthew Chen\Anaconda3\lib\site-packages\torch\utils\data\dataloader.py", line 279, in __iter__
  return _MultiProcessingDataLoaderIter(self)

File "C:\Users\Matthew Chen\Anaconda3\lib\site-packages\torch\utils\data\dataloader.py", line 719, in __init__
  w.start()

File "C:\Users\Matthew Chen\Anaconda3\lib\multiprocessing\process.py", line 112, in start
  self._popen = self._Popen(self)

File "C:\Users\Matthew Chen\Anaconda3\lib\multiprocessing\context.py", line 223, in _Popen
  return _default_context.get_context().Process._Popen(process_obj)

File "C:\Users\Matthew Chen\Anaconda3\lib\multiprocessing\context.py", line 322, in _Popen
  return Popen(process_obj)

File "C:\Users\Matthew Chen\Anaconda3\lib\multiprocessing\popen_spawn_win32.py", line 89, in __init__
  reduction.dump(process_obj, to_child)

File "C:\Users\Matthew Chen\Anaconda3\lib\multiprocessing\reduction.py", line 60, in dump
  ForkingPickler(file, protocol).dump(obj)

  BrokenPipeError: [Errno 32] Broken pipe

I'm not sure if I downloaded all the packages correctly, but this seems to be an error where the request to some server is blocked/timed out?

[Matthew Chen]

Nevermind! I realized this is a Windows-only issue (https://pytorch.org/tutorials/beginner/blitz/cifar10_tutorial.html). In order to prevent this error you'll have to change num-workers from 2 to 0.