Memcached 是一个高性能的分布式内存对象缓存系统,用于动态Web应用以减轻数据库负载。它通过在内存中缓存数据和对象来减少读取数据库的次数,从而提高动态、数据库驱动网站的速度。Memcached基于一个存储键/值对的hashmap。其守护进程(daemon )是用C写的,但是客户端可以用任何语言来编写,并通过memcached协议与守护进程通信。

https://github.com/gwhalin/Memcached-Java-Client

1、安装

源码安装

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wget http://www.danga.com/memcached/dist/memcached-1.2.0.tar.gz
wget http://www.monkey.org/~provos/libevent-1.2.tar.gz

yum安装基础依赖

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# yum install libevent libevent-devel -y
# find / -name libevent*|grep so
/usr/lib64/libevent_extra-1.4.so.2.1.3
/usr/lib64/libevent-1.4.so.2
/usr/lib64/libevent_core-1.4.so.2.1.3
/usr/lib64/libevent_extra-1.4.so.2
/usr/lib64/samba/libevents.so
/usr/lib64/libevent.so
/usr/lib64/libevent_core.so
/usr/lib64/libevent_extra.so
/usr/lib64/libevent_core-1.4.so.2
/usr/lib64/libevent-1.4.so.2.1.3

# tar -zxvf memcached-1.2.0.tar.gz
# cd memcached-1.2.0
# yum install gcc -y !!error==configure: error: no acceptable C compiler found in $PATH
# ./configure -with-libevent=/usr
# make && make install

检测安装是否成功

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[root@itr-nodetest02 memcached-1.2.0]#  ls -al /usr/local/bin/mem*
-rwxr-xr-x 1 root root 113124 May 23 10:00 /usr/local/bin/memcached
-rwxr-xr-x 1 root root 117479 May 23 10:00 /usr/local/bin/memcached-debug

2、启动Memcached服务

2.1.启动Memcache的服务器端:

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   #  /usr/local/bin/memcached -d -m 10 -u root -l 192.168.2.203 -p 11211 -c 256 -P /tmp/memcached.pid

-d选项是启动一个守护进程,
-m是分配给Memcache使用的内存数量,单位是MB,我这里是10MB,
-u是运行Memcache的用户,我这里是root,
-l是监听的服务器IP地址,如果有多个地址的话,我这里指定了服务器的IP地址192.168.0.200
-p是设置Memcache监听的端口,我这里设置了12000,最好是1024以上的端口,
-c选项是最大运行的并发连接数,默认是1024,我这里设置了256,按照你服务器的负载量来设定,
-P是设置保存Memcache的pid文件,我这里是保存在 /tmp/memcached.pid,

3、测试Memcached:

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   # lsof -i :11211
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
memcached 4142 root 3u IPv4 45398 0t0 TCP itr-nodetest02:memcache (LISTEN)
memcached 4142 root 4u IPv4 45399 0t0 UDP itr-nodetest02:memcache

# yum install telnet -y
# telnet 192.168.2.203 11211
Trying 192.168.2.203...
Connected to 192.168.2.203.
Escape character is '^]'.
^]
telnet> quit
Connection closed.
[root@itr-nodetest02 memcached-1.2.0]# ps -ef|grep memcached
root 4142 1 0 10:04 ? 00:00:00 /usr/local/bin/memcached -d -m 10 -u root -l 192.168.2.203 -p 11211 -c 256 -P /tmp/memcached.pid