mp_pool

mp_poll is an example of Python multiprocessing using a process Pool. Multiprocessing using a process Pool is a very simple way to implement parallel processing to increase performance.

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Send questions or comments to GraniteMountainInformaticsLLC@gmail.com.

"""

=pod

=head1 NAME

mp_pool.py

=head1 VERSION

202302190559

=head1 SYNOPSIS

python3 mp_pool.py

=head1 DESCRIPTION

This is an example of Python multiprocessing using a process Pool.

=cut

"""

# ######################################################################

# IMPORT CORE MODULES

# ######################################################################

import datetime

import glob

import multiprocessing

from multiprocessing import Pool

import os

import random

from random import random

import re

import sys

import time

from time import sleep

# ######################################################################

# IMPORT CUSTOM MODULES

# ######################################################################

sys.path.insert(0, os.environ['fp_gmi_pylib'])

import gmi_datetime

import gmi_debug

import gmi_file

import gmi_string

import gmi_tdapi

# ######################################################################

# DECLARE GLOBAL VARIABLES

# ######################################################################

# DECLARE FUNCTIONS

# ######################################################################

"""

=pod

=head1 FUNCTIONS

=cut

"""

=pod

=head2 mp_function(mp_args)

Execute the multiprocess function with the specified argument.

=cut

"""

def mp_function(mp_args):

# get the arguments

i, seconds = mp_args

# get the process id

pid = multiprocessing.current_process().pid

print(f"# [{pid}] mp_function({mp_args})", flush=True)

sleep(seconds)

return f"[{pid}] mp_function({mp_args}) slept for {seconds} seconds"

# ######################################################################

# MAIN

# ######################################################################

"""

The following "if __name__ == '__main__':" statement is a conditional

block explicitly identifies code to execute when your file is executed

as a script but not if the file is imported as a module.

"""

if __name__ == '__main__':

# print the command line

gmi_debug.print_sys_argv()

# print the cpu count

print(f"# CPU Count = {multiprocessing.cpu_count()}")

# set the mulitprocessing iteration argument

mp_args = []

for i in range(10):

mp_args.append([i, int(10 * random())])

# create the process pool

with Pool() as pool:

# iterate the mulitiprocess function over the arguments

for result in pool.map(mp_function, mp_args):

print(f"# {result}", flush=True)

"""

=pod

=head1 REFERENCE

=head1 REQUIRES

=head1 INSTALLATION

=head1 SEE ALSO

=head1 AUTHOR

Granite Mountain Informatics LLC

=head1 COPYRIGHT

=head1 PROPRIETARY SOFTWARE LICENSE

=head1 CHANGE HISTORY

=head1 TO DO

=cut

"""

The mp_pool.py program can be executed using the following commands in a linux shell script:

clear

fs_pypod='/Users/michaelhackerott/Documents/Granite Mountain Informatics LLC/Python/pypod/202302151410/pypod.py'

#echo "fs_pypod='${fs_pypod}'"

fp_pylib=`pwd`

#echo "fp_pylib='${fp_pylib}'"

function pypod()

{

rm -rf "${fp_pylib}/${1}.html"

python3 "${fs_pypod}" "${fp_pylib}/${1}"

open -a 'Google Chrome' "${fp_pylib}/${1}.html"

}

pypod mp_pool.py

export fp_gmi_pylib="/Users/michaelhackerott/Documents/Granite Mountain Informatics LLC/Python/gmi_pylib/202302151416"

python3 mp_pool.py

The output of the executed program:

% ./mp_pool.sh

/Users/michaelhackerott/Documents/Granite Mountain Informatics LLC/Python/pypod/202302151410/pypod.py /Users/michaelhackerott/Documents/Granite Mountain Informatics LLC/Python/mp_pool/202302190559/mp_pool.py

mp_pool.py

# CPU Count = 8

# [9144] mp_function([0, 9])

# [9146] mp_function([1, 1])

# [9145] mp_function([2, 6])

# [9147] mp_function([3, 2])

# [9148] mp_function([4, 5])

# [9149] mp_function([5, 0])

# [9149] mp_function([6, 5])

# [9151] mp_function([7, 5])

# [9150] mp_function([8, 3])

# [9146] mp_function([9, 9])

# [9144] mp_function([0, 9]) slept for 9 seconds

# [9146] mp_function([1, 1]) slept for 1 seconds

# [9145] mp_function([2, 6]) slept for 6 seconds

# [9147] mp_function([3, 2]) slept for 2 seconds

# [9148] mp_function([4, 5]) slept for 5 seconds

# [9149] mp_function([5, 0]) slept for 0 seconds

# [9149] mp_function([6, 5]) slept for 5 seconds

# [9151] mp_function([7, 5]) slept for 5 seconds

# [9150] mp_function([8, 3]) slept for 3 seconds

# [9146] mp_function([9, 9]) slept for 9 seconds

The mp_pool.py documentation: