python-multiprocessing

问题 So I'm trying to use multiprocessing Manager on a dict of dicts, this was my initial try: from multiprocessing import Process, Manager def task(stat): test['z'] += 1 test['y']['Y0'] += 5 if __name__ == '__main__': test = Manager().dict({'x': {'X0': 10, 'X1': 20}, 'y': {'Y0': 0, 'Y1': 0}, 'z': 0}) p = Process(target=task, args=(test,)) p.start() p.join() print(test) of course when I run this, the output is not what I expect, z updates correctly while y is unchanged! This is the output: {'x': {

问题 I am using python 3.6.7 with Ubuntu 18.04 After running the following script in which every process has its own shared lock : from multiprocessing import Process, Manager def foo(l1): with l1: print('lol') if __name__ == '__main__': processes = [] with Manager() as manager: for cluster in range(10): lock1 = manager.Lock() calc_args = (lock1, ) processes.append(Process(target=foo, args=calc_args)) for p in processes: p.start() for p in processes: p.join() I have strange exception: Process

问题 I am using python 3.6.7 with Ubuntu 18.04 After running the following script in which every process has its own shared lock : from multiprocessing import Process, Manager def foo(l1): with l1: print('lol') if __name__ == '__main__': processes = [] with Manager() as manager: for cluster in range(10): lock1 = manager.Lock() calc_args = (lock1, ) processes.append(Process(target=foo, args=calc_args)) for p in processes: p.start() for p in processes: p.join() I have strange exception: Process

问题 I am trying to implement multiprocessing, but I am having difficulties accessing information from the object scans that I'm passing through the pool.map() function Before multiprocessing (this works perfectly): for sc in scans: my_file = scans[sc].resources['DICOM'].files[0] After multiprocessing (does not work, error shown below): def process(x): my_file = x.resources['DICOM'].files[0] def another_method(): ... pool = Pool(os.cpu_count()) pool.map(process, [scans[sc] for sc in scans])

问题 I am trying to implement multiprocessing, but I am having difficulties accessing information from the object scans that I'm passing through the pool.map() function Before multiprocessing (this works perfectly): for sc in scans: my_file = scans[sc].resources['DICOM'].files[0] After multiprocessing (does not work, error shown below): def process(x): my_file = x.resources['DICOM'].files[0] def another_method(): ... pool = Pool(os.cpu_count()) pool.map(process, [scans[sc] for sc in scans])

问题 I am using Python 3.7 on Windows. What I am trying to do: - lock a method of an instance of a class, when another process has acquired that same lock. Attempts: I have already successfully done this, but I don't want a global variable here for the lock, but instead one completely internal to the class from multiprocessing import Lock, freeze_support,Pool from time import sleep def do_work(name): print(name+' waiting for lock to work...',end='') sleep(2) with lock: print('done!') print(name+'

问题 I am using Python 3.7 on Windows. What I am trying to do: - lock a method of an instance of a class, when another process has acquired that same lock. Attempts: I have already successfully done this, but I don't want a global variable here for the lock, but instead one completely internal to the class from multiprocessing import Lock, freeze_support,Pool from time import sleep def do_work(name): print(name+' waiting for lock to work...',end='') sleep(2) with lock: print('done!') print(name+'

问题 I am using Python 3.7 on Windows. What I am trying to do: - lock a method of an instance of a class, when another process has acquired that same lock. Attempts: I have already successfully done this, but I don't want a global variable here for the lock, but instead one completely internal to the class from multiprocessing import Lock, freeze_support,Pool from time import sleep def do_work(name): print(name+' waiting for lock to work...',end='') sleep(2) with lock: print('done!') print(name+'

问题 Below is my python script. import multiprocessing # We must import this explicitly, it is not imported by the top-level # multiprocessing module. import multiprocessing.pool import time from random import randint class NoDaemonProcess(multiprocessing.Process): # make 'daemon' attribute always return False def _get_daemon(self): return False def _set_daemon(self, value): pass daemon = property(_get_daemon, _set_daemon) # We sub-class multiprocessing.pool.Pool instead of multiprocessing.Pool #

问题 I have a class with the following method: def get_add_new_links(self, max_num_links): self.get_links_m2(max_num_links) processes = mp.cpu_count() pool = mp.Pool(processes=processes) func = partial(worker, self) with open(os.path.join(self.report_path, "links.txt"), "r") as f: reports = pool.map(func, f.readlines()) pool.close() pool.join() where get_links_m2 is another method that creates the file "links.txt". The worker is: def worker(obje, link): doc, rep = obje.get_info_m2(link) obje.add