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Parallel python

Among the many libraries for parallel processing in python I chose what seemed to have one of the simpler interfaces - Parallel Python.

There is one trick that is not apparent from the docs: The function you call has to be 'self sufficient'. You basically have to write up the function you call as if it were a script. So the function has to have the imports etc within itself.

This is not a biggie, but it gets confusing until you figure it out.

Original code:

# module x -----------------
import a
import b

def f1(g):
 f2
 f3

def f2():

def f3():

# Calling script
import x

x.f1(2)
x.f1(4)
x.f1(6)
x.f1(8)



Parallelized code
# module px ------------------------------
def pf(g)
 import x <------ NOTE THIS. ALL IMPORTS AND OTHER FUNS HAVE TO BE WITHIN THIS FUN
 x.f(g)

# New calling script
import pp
import px

ppservers = ()
job_server = pp.Server(ppservers=ppservers)

jobs = []
jobs.append(job_server.submit(px.pf, (2,))
jobs.append(job_server.submit(px.pf, (4,))
jobs.append(job_server.submit(px.pf, (6,))
jobs.append(job_server.submit(px.pf, (8,))
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