使用Python操作Memcached

1、安装

yum install memcached
easy_install python-memcached

2、操作memcached

import memcache
mc = memcache.Client(['127.0.0.1:12000'],debug=True)
mc.set('name','luo',60)
print mc.get('name')
mc.delete('name')　

3、监控脚本

"""
Server Density Agent Plugin for memcached
This script requires a config entry in the agent config
[Memcached]
host = '127.0.0.1'
port = 12000
"""

import sys
import telnetlib
import re
import socket
import logging
import json
import time


class Memcached:
    def __init__(self, agentConfig, checksLogger, rawConfig):
        self.agentConfig = agentConfig
        self.checksLogger = checksLogger
        self.rawConfig = rawConfig

    def run(self):
        stats = {}

        if hasattr(self.rawConfig['Memcached'], 'host'):
            host = self.rawConfig['Memcached']['host']
        else:
            host = '127.0.0.1'

        if hasattr(self.rawConfig['Memcached'], 'port'):
            port = self.rawConfig['Memcached']['port']
        else:
            port = 12000

        try:
            telnet = telnetlib.Telnet()
            telnet.open(host, port)
            telnet.write('stats\r\n')

            out = telnet.read_until("END")

            telnet.write('quit\r\n')
            telnet.close()
        except socket.error, reason:
            sys.stderr.write("%s\n" % reason)
            sys.stderr.write("Is memcached running?\n")
            sys.stderr.write("Host: %s Port: %s\n" % (host, port))
            return stats

        # Current / Total
        stats['curr_items'] = int(re.search("curr_items (\d+)", out).group(1))
        stats['total_items'] = int(re.search("total_items (\d+)", out).group(1))

        # Memory Usgae
        stats['limit_maxbytes'] = int(re.search("limit_maxbytes (\d+)", out).group(1))
        stats['bytes'] = int(re.search("bytes (\d+)", out).group(1))

        # Network Traffic
        stats['bytes_read'] = int(re.search("bytes_read (\d+)", out).group(1))
        stats['bytes_written'] = int(re.search("bytes_written (\d+)", out).group(1))

        # Connections
        stats['curr_connections'] = int(re.search("curr_connections (\d+)", out).group(1))
        stats['total_connections'] = int(re.search("total_connections (\d+)", out).group(1))

        # Hits / Misses
        stats['cmd_get'] = int(re.search("cmd_get (\d+)", out).group(1))
        stats['cmd_set'] = int(re.search("cmd_set (\d+)", out).group(1))
        stats['get_hits'] = int(re.search("get_hits (\d+)", out).group(1))
        stats['get_misses'] = int(re.search("get_misses (\d+)", out).group(1))
        stats['delete_hits'] = int(re.search("delete_hits (\d+)", out).group(1))
        stats['delete_misses'] = int(re.search("delete_misses (\d+)", out).group(1))
        stats['incr_hits'] = int(re.search("incr_hits (\d+)", out).group(1))
        stats['decr_hits'] = int(re.search("decr_hits (\d+)", out).group(1))
        stats['incr_misses'] = int(re.search("incr_misses (\d+)", out).group(1))
        stats['decr_misses'] = int(re.search("decr_misses (\d+)", out).group(1))

        # Evictions
        stats['evictions'] = int(re.search("evictions (\d+)", out).group(1))
        stats['reclaimed'] = int(re.search("reclaimed (\d+)", out).group(1))

        return stats


if __name__ == '__main__':
    """
    Standalone test configuration
    """
    raw_agent_config = {
        'Memcached': {
            'host': '127.0.0.1',
            'port': 12000,
        }
    }

    main_checks_logger = logging.getLogger('Memcached')
    main_checks_logger.setLevel(logging.DEBUG)
    main_checks_logger.addHandler(logging.StreamHandler(sys.stdout))
    host_check = Memcached({}, main_checks_logger, raw_agent_config)

    while True:
        try:
            print json.dumps(host_check.run(), indent=4, sort_keys=True)
        except:
            main_checks_logger.exception("Unhandled exception")
        finally:
            time.sleep(60)

可以把记录写入日志文件，用gnuplot或者rrdtool绘成图片会更好

4、压力测试脚本

#!/usr/bin/python2
import memcache
import time
def test_set():
    m = memcache.Client(['127.0.0.1:12000'],debug=True)
    for i in range(100000):
        m.set('name'+ str(i) ,'problem'+str(i),5000)
    return

def test_get():
    m = memcache.Client(['127.0.0.1:12000'],debug=True)
    for i in range(100000):
        m.get('name'+ str(i))
    return
def test_delete():
    m = memcache.Client(['127.0.0.1:12000'],debug=True)
    for i in range(100000):
        m.delete('name'+ str(i))
    return
def bench(desc):
    start=time.clock()
    desc()
    stop=time.clock()
    diff=stop-start
    print "%s has token %s" % (desc.func_name,str(diff))
if __name__=='__main__':
    bench(test_set)
    bench(test_get)
    #bench(test_delete)

10W次读取需要1s多，读取也是1s多 ，5-6W QPS问题不大