Cannot start a new process

[raylooi]

(base) D:\codes\Person-Attribute-Recognition-MarketDuke-master>python train.py --data-path dataset --dataset duke --model resnet50

Traceback (most recent call last):
File "", line 1, in
File "D:\Anaconda\lib\multiprocessing\spawn.py", line 105, in spawn_main
exitcode = _main(fd)
File "D:\Anaconda\lib\multiprocessing\spawn.py", line 114, in _main
prepare(preparation_data)
File "D:\Anaconda\lib\multiprocessing\spawn.py", line 225, in prepare
_fixup_main_from_path(data['init_main_from_path'])
File "D:\Anaconda\lib\multiprocessing\spawn.py", line 277, in _fixup_main_from_path
Traceback (most recent call last):
File "train.py", line 101, in
run_name="mp_main")
File "D:\Anaconda\lib\runpy.py", line 263, in run_path
images, indices, labels, ids, cams, names = next(iter(dataloaders['train']))
pkg_name=pkg_name, script_name=fname) File "D:\Anaconda\lib\site-packages\torch\utils\data\dataloader.py", line 193, in iter

  File "D:\Anaconda\lib\runpy.py", line 96, in _run_module_code

return _DataLoaderIter(self)
File "D:\Anaconda\lib\site-packages\torch\utils\data\dataloader.py", line 469, in init
mod_name, mod_spec, pkg_name, script_name)
w.start() File "D:\Anaconda\lib\runpy.py", line 85, in _run_code

  File "D:\Anaconda\lib\multiprocessing\process.py", line 112, in start

exec(code, run_globals)
File "D:\codes\Person-Attribute-Recognition-MarketDuke-master\train.py", line 101, in
self._popen = self._Popen(self)
images, indices, labels, ids, cams, names = next(iter(dataloaders['train'])) File "D:\Anaconda\lib\multiprocessing\context.py", line 223, in _Popen

  File "D:\Anaconda\lib\site-packages\torch\utils\data\dataloader.py", line 193, in __iter__

return _default_context.get_context().Process._Popen(process_obj)
return _DataLoaderIter(self) File "D:\Anaconda\lib\multiprocessing\context.py", line 322, in _Popen

File "D:\Anaconda\lib\site-packages\torch\utils\data\dataloader.py", line 469, in init
return Popen(process_obj)w.start()

File "D:\Anaconda\lib\multiprocessing\popen_spawn_win32.py", line 89, in init
File "D:\Anaconda\lib\multiprocessing\process.py", line 112, in start
reduction.dump(process_obj, to_child)self._popen = self._Popen(self)

File "D:\Anaconda\lib\multiprocessing\reduction.py", line 60, in dump
File "D:\Anaconda\lib\multiprocessing\context.py", line 223, in _Popen
ForkingPickler(file, protocol).dump(obj)return _default_context.get_context().Process._Popen(process_obj)

BrokenPipeError File "D:\Anaconda\lib\multiprocessing\context.py", line 322, in _Popen
: [Errno 32] Broken pipereturn Popen(process_obj)

File "D:\Anaconda\lib\multiprocessing\popen_spawn_win32.py", line 46, in init
prep_data = spawn.get_preparation_data(process_obj._name)
File "D:\Anaconda\lib\multiprocessing\spawn.py", line 143, in get_preparation_data
_check_not_importing_main()
File "D:\Anaconda\lib\multiprocessing\spawn.py", line 136, in _check_not_importing_main
is not going to be frozen to produce an executable.''')
RuntimeError:
An attempt has been made to start a new process before the
current process has finished its bootstrapping phase.

    This probably means that you are not using fork to start your
    child processes and you have forgotten to use the proper idiom
    in the main module:

        if __name__ == '__main__':
            freeze_support()
            ...

    The "freeze_support()" line can be omitted if the program
    is not going to be frozen to produce an executable.

[raylooi]

does this mean the train.py needs to add "if name == 'main': "?

as in

if name == 'main':
model = train_model(model, criterion, optimizer, exp_lr_scheduler,
num_epochs = args.num_epoch)

[raylooi]

but i still get the error. anyone knows what needs to be changed here?

[ljx6666]

@raylooi
Please put '' if name == ' main': '' before '' parser = argparse.ArgumentParser(description='Training') '', you can solve this problem.