针对永久不过期的key 批量设置过期时间

问题需求：
　　redis内存暴增，后来发现有很多设置永久不过期。

解决：查找出来之后针对前缀批量设置过期时间 （过期时间与开发沟通 保证服务不受影响）

 来源于网上杨一的代码   正好解决了我遇到的问题 在这里记录一下。 

1 # encoding: utf-8

import redis
import random
import string
import time
pool = redis.ConnectionPool(host='127.0.0.1', port=6379, password="123456", db=0)
r = redis.Redis(connection_pool=pool)

def random_str():
    return ''.join(random.choice(string.ascii_letters + string.digits) for _ in range(7))


def init_keys():
    start_time = time.time()
    for i in xrange(0, 20):
        key_name = 'dba_'+str(i)
        value_name = random_str()
        r.set(key_name, value_name)
    print 'initial keys successfully,use time:', time.time() - start_time


def del_keys_without_pipe():
    start_time = time.time()
    result_length = 0
    for key in r.scan_iter(match='rawdata_lastStatus_0015000200*', count=1000):
        r.delete(key)
        result_length += 1
    print "normal ways end at:", time.time() - start_time
    print "normal ways delete numbers:", result_length


def del_keys_with_pipe():
    start_time = time.time()
    result_length = 0
    pipe = r.pipeline()
    for key in r.scan_iter(match='rawdata_*_otherTrades', count=1000):
        pipe.expire(key,120)
        result_length += 1
        if result_length % 1000 == 0:
            pipe.execute()
        time.sleep(1)
    pip_time = time.time()
    print "use pipeline scan time ", time.time() - start_time
    pipe.execute()

    print "use pipeline end at:", time.time() - pip_time
    print "use pipeline ways delete numbers:", result_length


def main():
#    init_keys()
#    del_keys_without_pipe()
#    init_keys()
    del_keys_with_pipe()


if __name__ == '__main__':
    main()