multiprocessing

Error using pexpect and multiprocessing? error “TypError: cannot serialize '_io.TextIOWrapper' object”

拈花ヽ惹草 提交于 2021-02-10 20:01:35
问题 I have a Python 3.7 script on a Linux machine where I am trying to run a function in multiple threads, but when I try I receive the following error: Traceback (most recent call last): File "./test2.py", line 43, in <module> pt.ping_scanx() File "./test2.py", line 39, in ping_scanx par = Parallel(function=self.pingx, parameter_list=list, thread_limit=10) File "./test2.py", line 19, in __init__ self._x = self._pool.starmap(function, parameter_list, chunksize=1) File "/usr/local/lib/python3.7

Error using pexpect and multiprocessing? error “TypError: cannot serialize '_io.TextIOWrapper' object”

人盡茶涼 提交于 2021-02-10 20:00:14
问题 I have a Python 3.7 script on a Linux machine where I am trying to run a function in multiple threads, but when I try I receive the following error: Traceback (most recent call last): File "./test2.py", line 43, in <module> pt.ping_scanx() File "./test2.py", line 39, in ping_scanx par = Parallel(function=self.pingx, parameter_list=list, thread_limit=10) File "./test2.py", line 19, in __init__ self._x = self._pool.starmap(function, parameter_list, chunksize=1) File "/usr/local/lib/python3.7

module path lost in multiprocessing spawn (ModuleNotFoundError)

六眼飞鱼酱① 提交于 2021-02-10 17:48:42
问题 Say we have a script that works with no problem: import module1 class SomeClass(object): def __init__(self): self.m = module1() s = SomeCLass() However if I use multiprocessing module with "spawn" context: import module1 import multiprocessing as mp class SomeClass(object): def __init__(self): self.m = module1() s = SomeCLass() ctx = mp.get_context('spawn') proc = ctx.Process(target=SomeClass, kwargs={}) proc.daemon = True proc.start() I get the following error at proc.start() :

module path lost in multiprocessing spawn (ModuleNotFoundError)

我与影子孤独终老i 提交于 2021-02-10 17:47:59
问题 Say we have a script that works with no problem: import module1 class SomeClass(object): def __init__(self): self.m = module1() s = SomeCLass() However if I use multiprocessing module with "spawn" context: import module1 import multiprocessing as mp class SomeClass(object): def __init__(self): self.m = module1() s = SomeCLass() ctx = mp.get_context('spawn') proc = ctx.Process(target=SomeClass, kwargs={}) proc.daemon = True proc.start() I get the following error at proc.start() :

Python - “can't pickle thread.lock” error when creating a thread under a multiprocess in Windows

浪子不回头ぞ 提交于 2021-02-10 16:00:00
问题 I'm getting stuck on what I think is a basic multiprocess and threading issue. I've got a multiprocess set up, and within this a thread. However, when I set up the thread class within the init function, I get the following error: "TypeError: can't pickle thread.lock objects". However, this does not happen if the thread is set up outside of the init function. Does anyone know why this is happening? Note I'm using Windows. Some code is below to illustrate the issue. As typed below, it runs fine

How to use Multiprocessing Queue with Lock

微笑、不失礼 提交于 2021-02-10 14:31:00
问题 The posted code starts two async Processes . The first publisher Process publishes data to the Queue , the second subscriber Process reads the data from the Queue and logs it to console. To make sure the Queue is not accessed at the same time, before getting the data from the Queue , the subscribe function first executes lock.acquire() , then gets the data with data = q.get() and finally releases the lock with the lock.release() statement. The same locking-releasing sequence is used in

Why calculating factorial using multiprocessing is slower than using recursion?

落爺英雄遲暮 提交于 2021-02-10 12:05:05
问题 I'm trying to find a faster way to calculate factorial. In the following code, I first use recursion method , and then I use another method by dividing the whole operation into smaller calculations and then run them in parallel. Here's my code: #!/usr/bin/env python3 import time from multiprocessing import Pool import itertools def fact(n): if n==1: return 1 else: a=n*fact(n-1) return a def divid(start ,end): m=1 for i in range(start,end+1): m=m*i return m pool=Pool() a=time.time() res=fact

Why calculating factorial using multiprocessing is slower than using recursion?

岁酱吖の 提交于 2021-02-10 12:04:25
问题 I'm trying to find a faster way to calculate factorial. In the following code, I first use recursion method , and then I use another method by dividing the whole operation into smaller calculations and then run them in parallel. Here's my code: #!/usr/bin/env python3 import time from multiprocessing import Pool import itertools def fact(n): if n==1: return 1 else: a=n*fact(n-1) return a def divid(start ,end): m=1 for i in range(start,end+1): m=m*i return m pool=Pool() a=time.time() res=fact

Why calculating factorial using multiprocessing is slower than using recursion?

生来就可爱ヽ(ⅴ<●) 提交于 2021-02-10 12:04:04
问题 I'm trying to find a faster way to calculate factorial. In the following code, I first use recursion method , and then I use another method by dividing the whole operation into smaller calculations and then run them in parallel. Here's my code: #!/usr/bin/env python3 import time from multiprocessing import Pool import itertools def fact(n): if n==1: return 1 else: a=n*fact(n-1) return a def divid(start ,end): m=1 for i in range(start,end+1): m=m*i return m pool=Pool() a=time.time() res=fact

Tkinter is opening multiple GUI windows upon file selection with multiprocessing, when only one window should exist

强颜欢笑 提交于 2021-02-10 08:16:01
问题 I have primary.py: from tkinter import * from tkinter.filedialog import askopenfilename from tkinter import ttk import multiprocessing as mp import other_script class GUI: def __init__(self, master): self.master = master def file_select(): path = askopenfilename() if __name__ == '__main__': queue = mp.Queue() queue.put(path) import_ds_proc = mp.Process(target=other_script.dummy, args=(queue,)) import_ds_proc.daemon = True import_ds_proc.start() # GUI root = Tk() my_gui = GUI(root) # Display