I'd like to run multiple python scripts in parallel and start them from a master script. I did find solutions for this in previously asked questions, however, none of these worked if the scripts running in parallel contained loops. Let's for example define two scripts.
Script 1:
array_1 = []
x = 0
while True:
array_1.append(x)
x = x 1
Script 2:
array_2 = []
x = 0
while True:
array_2.append(x)
x = x 1
Now I want to run both processes simultaneously. Previous solutions suggested the following code for a master script:
import script_1, script_2
exec(open(script_1))
exec(open(script_2))
While this is a solution for starting scripts from within another script, however, this will not run the two scripts in parallel. What should such a master script actually look like ?
Thanks for your suggestions!
Edit
I tried the following threading approach:
def function_1():
print('function 1 started...')
while True:
print('1')
sleep(1)
def function_2():
print('function 2 started...')
while True:
print('2')
sleep(1)
thread_1 = Thread(target=function_1())
thread_2 = Thread(target=function_2())
thread_1.start()
thread_2.start()
thread_1.join()
thread_2.join()
print("thread finished")
It doesn't work, only the first function gets started so I get the following output:
function 1 started...
1
1
1
1
1
1
CodePudding user response:
When you want to spawn a new thread, you need to pass the address of the function you want the thread to execute, and not to call it. What you are doing here is essentially spawning a new thread that immediately calls function_1()
which of course runs forever.
Also, you won't be able to reach this line of code:
print("thread finished")
As the threads are executing a while loop - forever, so it is redundent..
from time import sleep
from threading import Thread
def function_1():
print('function 1 started...')
while True:
print('1')
sleep(1)
def function_2():
print('function 2 started...')
while True:
print('2')
sleep(1)
thread_1 = Thread(target=function_1)
thread_2 = Thread(target=function_2)
thread_1.start()
thread_2.start()
thread_1.join()
thread_2.join()
# print("thread finished") - redundant