Python - multiprocessing.Pool( ).map( )

Original Sources:

• Youtube by ‘Real Python’

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Used in this file:

• Python - map

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Δttention:

multiprocessing.Pool().map() does not accept lambda functions

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~ Ex.:

import multiprocessing
 
a = (1,2,3,4,5,6,7)
 
def mappiing(x):
	import time.sleep
	time.sleep(1)
	return x+1
 
pool = multiprocessing.Pool()
b = pool.map(mappiing,a) 
#Should take 7 seconds it takes WAY LESS, 
#because the map is beind executed 
#in parallel with multiple processes

Optional: How many processes are runned at the same time:

import multiprocessing
pool = multiprocessing.Pool(processes = 4)

Optional: How may task can a process take before starting a new process

import multiprocessing
pool = multiprocessing.Pool(maxtasksperchild = 10)
# A process (~es. process number 17403) does 10 task 
# (~es.: executes 10 mapping from start to end than)
# kills itself and a new process (~es.: 17408) starts

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