tractor/examples/parallelism/concurrent_futures_primes.py

62 lines
1.4 KiB
Python

'''
The pure-stdlib `concurrent.futures.ProcessPoolExecutor`
primes demo (from the std docs) verbatim; the baseline twin
of `concurrent_actors_primes.py`.
The `async def main()` + `trio.run()` shim at the bottom only
exists so the docs-example test runner can exercise this
script; the executor code itself is untouched stdlib fare.
'''
import time
import concurrent.futures
import math
import trio
PRIMES = [
112272535095293,
112582705942171,
112272535095293,
115280095190773,
115797848077099,
1099726899285419]
def is_prime(n):
if n < 2:
return False
if n == 2:
return True
if n % 2 == 0:
return False
sqrt_n = int(math.floor(math.sqrt(n)))
for i in range(3, sqrt_n + 1, 2):
if n % i == 0:
return False
return True
def check_primes():
with concurrent.futures.ProcessPoolExecutor() as executor:
start = time.time()
for number, prime in zip(PRIMES, executor.map(is_prime, PRIMES)):
print('%d is prime: %s' % (number, prime))
print(f'processing took {time.time() - start} seconds')
async def main() -> None:
# thin shim: the pool blocks this (sole) trio task
# which is just fine for a one-shot baseline script.
check_primes()
if __name__ == '__main__':
start = time.time()
trio.run(main)
print(f'script took {time.time() - start} seconds')