Wait for all python processes to finish

Question

I'm starting several python processes with downloads in a loop that calls this piece of code:

startTimeMillis = int(round(time.time() * 1000))

for i in range(10):
        p = multiprocessing.Process(target=performCurl, args =("http://www.google.com/d", i, ))
        p.start()


endTimeMillis = int(round(time.time() * 1000))
totalTimeSeconds = (endTimeMillis - startTimeMillis)
print "The whole process took ", str(totalTimeSeconds)

I want to check the time it takes for all the processes to finish, so how would I make the last part of the code to wait for all the processes?

Answer 1

Use p.join() to wait for a process to terminate

all_processes = [multiprocessing.Process(...) for ... in ...]
for p in all_processes:
  p.start()

for p in all_processes:
  p.join()