I want to use multiprocessing module with sqlAlchemy in my custom class. Here is the code: from sqlalchemy import create_engine engine = create_engine(f'mysql+pymysql://a:b@localhost:3306/', serv...

Running two threads with the Multiprocessing library in Python, putting items into a queue in the daughter thread and getting them from the parents, hangs on the last item. The question is why is t...

I got the error whenever I use the torch.multiprocessing.spawn to parallelize over multiple GPUs, including the code examples in Parallel and Distributed Training tutorials. Exception: process 0 t...

consider the following server code : from multiprocessing.managers import BaseManager, BaseProxy def baz(aa) : print "aaa" l = [] for i in range(3) : l.append(aa) return l class SolverMana...

I want to execute the following two functions at exactly the same time. from multiprocessing import Process import os import datetime def func_1(title): now = datetime.datetime.now() print "hel...

I am trying to migrate a bash script to Python. The bash script runs multiple OS commands in parallel and then waits for them to finish before resuming, ie: command1 & command2 & . command...

I have the following class that is shared between multiple consumers (using producer/consumer methodology). My question involves the methods called on this class. Do I need to implement locks or is...

I want to parallelize a task (progresser()) for a range of input parameters (L). The progress of each task should be monitored by an individual progress bar in the terminal. I'm using the tqdm pack...

To identify the step that is using most of the computation time, I ran cProfile and got the following result: ncalls tottime percall cumtime percall filename:lineno(function) 1 0.014 0.014 216.0...

My question is how change this code so it will use only 4 sub-processes? TESTS="a b c d e" for f in $TESTS; do t=$[ ( $RANDOM % 5 ) + 1 ] sleep $t && echo $f $t & done wait...

I'm having this problem in python: I have a queue of URLs that I need to check from time to time if the queue is filled up, I need to process each item in the queue Each item in the queue must be...

I am trying to implement this tutorial on mutliprocessing in python, but when I tried to do my own task I get the following error: Traceback (most recent call last): >>> File "C:\Python27...

I'm basically following the last code from this thread Is there any faster way for downloading multiple files from s3 to local folder?. I adapted it to my problem which is extract files from s3 int...

I expect the following code to print [{0: 100}], since it do the plus in updateList for a hundred time In turn, it prints [{0: 0}] what's the problem and how to rectify it? from multiprocessing im...

Background: I'm working a project which uses Django with a Postgres database. We're also using mod_wsgi in case that matters, since some of my web searches have made mention of it. On web form sub...

I'm using Python 3.6 and am trying to follow along with the very first example at the website below (full code also below) and am getting the below error: https://docs.python.org/3.6/library/multip...

I have a python function that takes in a multiprocessing.Lock object as an input and uses the acquire and release functions on it. Evaluating it with mypy returns the error Function multiprocessing...

I am very new to python and I encounter this error. CODE 1 : import multiprocessing as mp import os def calc(num1, num2): global addi def addi(num1, num2): print(num1+num2) m = mp.Process(tar...

I'm a go-newbie, so please be gentle. So I've been using mutexes in some of my code for a couple weeks now. I understand the concept behind it: lock access to a certain resource, interact with it...

I found that in Python 3.4, there are few different libraries for multiprocessing/threading: multiprocessing vs threading vs asyncio. But I don't know which one to use or is the "recommended o...

I am struggling to correctly parallelise a function using Cython. Basically, the problem is to bin some data. The actual code is a bit long, but in the end it does something like this: def bin_var(...

I'm doing a Django project and try to improve computing speed in backend. The task is something like a CPU-bound conversion process Here's my environment Python 3.6.1 Django 1.10 PostgreSQL 9.6...

I have three large lists. First contains bitarrays (module bitarray 0.8.0) and the other two contain arrays of integers. l1=[bitarray 1, bitarray 2, ... ,bitarray n] l2=[array 1, array 2, ... , ar...

What are the fundamental differences between queues and pipes in Python's multiprocessing package? In what scenarios should one choose one over the other? When is it advantageous to use Pipe()? Wh...

How do I pass a dictionary to a function with Python's Multiprocessing? The Documentation: https://docs.python.org/3.4/library/multiprocessing.html#reference says to pass a dictionary, but I keep g...