gevent based concurrency for redis-py

gevent_concurrency_redis.py

import logging
logging.basicConfig(
    format='%(asctime)s,%(msecs)05.1f (%(funcName)s) %(message)s',
    datefmt='%H:%M:%S')
log = logging.getLogger()
log.setLevel(logging.INFO)
 
import threading
import os
import time
import gevent
import redis
import redis.connection
redis.connection.socket = gevent.socket
 
 
r = redis.StrictRedis()
p = r.connection_pool
 
 
def main():
    crongreenlet = gevent.spawn(cron)
    log.info("Spawning 500 greenlets connecting to Redis...")
    redisgreenlets = [gevent.spawn(ask_redis) for _ in xrange(500)]
    starttime = time.time()
    # Wait until all greenlets have started and connected.
    gevent.sleep(1)
    log.info("# active `threading` threads: %s" % threading.active_count())
    log.info("# Redis connections created: %s" % p._created_connections)
    log.info("# Redis connections in use: %s" % len(p._in_use_connections))
    log.info("# Redis connections available: %s" % len(p._available_connections))
    log.info("Waiting for Redis connection greenlets to terminate...")
    gevent.joinall(redisgreenlets)
    d = time.time() - starttime
    log.info("All Redis connection greenlets terminated. Duration: %.2f s." % d)
    crongreenlet.kill()
 
 
def ask_redis():
    # BRPOP returns (key, value) tuple or None
    assert r.brpop("list", timeout=1) is None
 
 
def cron():
    while True:
        log.info("Hello from cron greenlet.")
        gevent.sleep(0.2)
 
 
if __name__ == "__main__":
    main()