Threading with Python

fib.py

def fib(n):
    if n <= 2:
        return 1
    else:
        return fib(n-1) + fib(n-2)

multiprocessing.py

import urllib2
from multiprocessing.dummy import Pool as ThreadPool
import time

urls = [
    'http://www.python.org',
    'http://www.python.org/about/',
    'http://www.onlamp.com/pub/a/python/2003/04/17/metaclasses.html',
    'http://www.python.org/doc/',
    'http://www.python.org/download/',
    'http://www.python.org/getit/',
    'http://www.python.org/community/',
    'https://wiki.python.org/moin/',
    'http://planet.python.org/',
    'https://wiki.python.org/moin/LocalUserGroups',
    'http://www.python.org/psf/',
    'http://docs.python.org/devguide/',
    'http://www.python.org/community/awards/'
    # etc..
]

# Make the Pool of workers
pool = ThreadPool(4)
# Open the urls in their own threads
# and return the results
results = pool.map(urllib2.urlopen, urls)
# close the pool and wait for the work to finish
pool.close()
pool.join()

#%%


class Timer():

    @classmethod
    def start(cls):
        cls._start = time.time()

    @classmethod
    def elapsed(cls):
        return time.time() - cls._start

    @classmethod
    def show(cls):
        print "*** Elapsed: %0.5f" % cls.elapsed()

#%% --- Single thread ----- #
Timer.start()
results = []
for url in urls:
    result = urllib2.urlopen(url)
    results.append(result)
Timer.show()

#%% ------- 4 Pool ------- #
Timer.start()
pool = ThreadPool(4)
results = pool.map(urllib2.urlopen, urls)
Timer.show()

#%% ------- 8 Pool ------- #
Timer.start()
pool = ThreadPool(8)
results = pool.map(urllib2.urlopen, urls)
Timer.show()

#%% ------- 13 Pool ------- #
Timer.start()
pool = ThreadPool(13)
results = pool.map(urllib2.urlopen, urls)
Timer.show()


#    Single thread:  9.35082 sec
#           4 Pool:  3.09248 sec
#           8 Pool:  2.08774 sec
#          13 Pool:  1.67926 sec

perf1.py

# perf1.py
# Time of a long running request

from socket import *
import time

sock = socket(AF_INET, SOCK_STREAM)
sock.connect(('localhost', 25000))

while True:
    start = time.time()
    sock.send(b'30')
    resp =sock.recv(100)
    end = time.time()
    print(end-start)

perf2.py

# perf2.py
# requests/sec of fast requests

from socket import *
import time

sock = socket(AF_INET, SOCK_STREAM)
sock.connect(('localhost', 25000))

n = 0

from threading import Thread
def monitor():
    global n
    while True:
        time.sleep(1)
        print(n, 'reqs/sec')
        n = 0
Thread(target=monitor).start()

while True:
    sock.send(b'1')
    resp =sock.recv(100)
    n += 1

pool.py

"""
A more realistic thread pool example

Practical threaded programming with Python
http://www.ibm.com/developerworks/aix/library/au-threadingpython/
"""

import time
import threading
import Queue
import urllib2
#%%


class Consumer(threading.Thread):

    def __init__(self, queue):
        threading.Thread.__init__(self)
        self._queue = queue

    def run(self):
        while True:
            content = self._queue.get()
            if isinstance(content, str) and content == 'quit':
                break
            urllib2.urlopen(content)
        print 'Bye byes!'


def Producer():
    urls = [
        'http://www.python.org', 'http://www.yahoo.com'
        'http://www.scala.org', 'http://www.google.com'
        # etc..
    ]
    queue = Queue.Queue()
    worker_threads = build_worker_pool(queue, 4)
    start_time = time.time()

    # Add the urls to process
    for url in urls:
        queue.put(url)
    # Add the poison pillv
    for worker in worker_threads:
        queue.put('quit')
    for worker in worker_threads:
        worker.join()

    print 'Done! Time taken: {}'.format(time.time() - start_time)


def build_worker_pool(queue, size):
    workers = []
    for _ in range(size):
        worker = Consumer(queue)
        worker.start()
        workers.append(worker)
    return workers
#%%

if __name__ == '__main__':
    Producer()

server.py

# server.py
# Fib microservice

from socket import *
from fib import fib
from threading import Thread

def fib_server(address):
    sock = socket(AF_INET, SOCK_STREAM)
    sock.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
    sock.bind(address)
    sock.listen(5)
    while True:
        client, addr = sock.accept()
        print("Connection", addr)
        fib_handler(client)

def fib_handler(client):
    while True:
        req = client.recv(100)
        if not req:
            break
        n = int(req)
        result = fib(n)
        resp = str(result).encode('ascii') + b'\n'
        client.send(resp)
    print("Closed")

fib_server(('',25000))

server_threading.py

# server.py
# Fib microservice

from socket import *
from fib import fib
from threading import Thread

def fib_server(address):
    sock = socket(AF_INET, SOCK_STREAM)
    sock.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
    sock.bind(address)
    sock.listen(5)
    while True:
        client, addr = sock.accept()
        print("Connection", addr)
        Thread(target=fib_handler, args=(client,), daemon=True).start()

def fib_handler(client):
    while True:
        req = client.recv(100)
        if not req:
            break
        n = int(req)
        result = fib(n)
        resp = str(result).encode('ascii') + b'\n'
        client.send(resp)
    print("Closed")

fib_server(('',25000))

server_threading_pool.py

# server.py
# Fib microservice

from socket import *
from fib import fib
from threading import Thread
from concurrent.futures import ProcessPoolExecutor as Pool

pool = Pool(4)

def fib_server(address):
    sock = socket(AF_INET, SOCK_STREAM)
    sock.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
    sock.bind(address)
    sock.listen(5)
    while True:
        client, addr = sock.accept()
        print("Connection", addr)
        Thread(target=fib_handler, args=(client,), daemon=True).start()

def fib_handler(client):
    while True:
        req = client.recv(100)
        if not req:
            break
        n = int(req)
        future = pool.submit(fib, n)
        result = future.result()
        resp = str(result).encode('ascii') + b'\n'
        client.send(resp)
    print("Closed")

fib_server(('',25000))

threading.py

"""
Standard Producer/Consumer Threading Pattern
"""

import time
import threading
import Queue
#%%


class Consumer(threading.Thread):

    def __init__(self, queue):
        threading.Thread.__init__(self)
        self._queue = queue

    def run(self):
        while True:
            # queue.get() blocks the current thread until
            # an item is retrieved.
            msg = self._queue.get()
            # Checks if the current message is
            # the "Poison Pill"
            if isinstance(msg, str) and msg == 'quit':
                # if so, exists the loop
                break
            # "Processes" (or in our case, prints) the queue item
            print "I'm a thread, and I received %s!!" % msg
        # Always be friendly!
        print 'Bye byes!'


def Producer():
    # Queue is used to share items between
    # the threads.
    queue = Queue.Queue()

    # Create an instance of the worker
    worker = Consumer(queue)
    # start calls the internal run() method to
    # kick off the thread
    worker.start()

    # variable to keep track of when we started
    start_time = time.time()
    # While under 5 seconds..
    while time.time() - start_time < 5:
        # "Produce" a piece of work and stick it in
        # the queue for the Consumer to process
        queue.put('something at %s' % time.time())
        # Sleep a bit just to avoid an absurd number of messages
        time.sleep(1)

    # This the "poison pill" method of killing a thread.
    queue.put('quit')
    # wait for the thread to close down
    worker.join()
#%%

if __name__ == '__main__':
    Producer()