CentOS下Memcache服务器端的安装 

服务器端主要是安装memcache服务器端，目前的最新版本是 memcached-1.3.0 。 
下载：http://www.danga.com/memcached/dist/memcached-1.2.2.tar.gz 
另外，Memcache用到了libevent这个库用于Socket的处理，所以还需要安装libevent，libevent的最新版本是libevent-1.3。（如果你的系统已经安装了libevent，可以不用安装） 
官网：http://www.monkey.org/~provos/libevent/ 
下载：http://www.monkey.org/~provos/libevent-1.3.tar.gz

用wget指令直接下载这两个东西.下载回源文件后。 
1.先安装libevent。这个东西在配置时需要指定一个安装路径，即./configure –prefix=/usr；然后make；然后make install； 
2.再安装memcached，只是需要在配置时需要指定libevent的安装路径即./configure –with-libevent=/usr；然后make；然后make install； 
这样就完成了Linux下Memcache服务器端的安装。详细的方法如下：

1.分别把memcached和libevent下载回来，放到 /tmp 目录下： 
# cd /tmp 
# wget http://www.danga.com/memcached/dist/memcached-1.2.0.tar.gz 
# wget http://www.monkey.org/~provos/libevent-1.2.tar.gz

2.先安装libevent： 
# tar zxvf libevent-1.2.tar.gz 
# cd libevent-1.2 
# ./configure –prefix=/usr 
# make 
# make install

3.测试libevent是否安装成功： 
# ls -al /usr/lib | grep libevent 
lrwxrwxrwx 1 root root 21 11?? 12 17:38 libevent-1.2.so.1 -> libevent-1.2.so.1.0.3 
-rwxr-xr-x 1 root root 263546 11?? 12 17:38 libevent-1.2.so.1.0.3 
-rw-r–r– 1 root root 454156 11?? 12 17:38 libevent.a 
-rwxr-xr-x 1 root root 811 11?? 12 17:38 libevent.la 
lrwxrwxrwx 1 root root 21 11?? 12 17:38 libevent.so -> libevent-1.2.so.1.0.3 
还不错，都安装上了。

4.安装memcached，同时需要安装中指定libevent的安装位置： 
# cd /tmp 
# tar zxvf memcached-1.2.0.tar.gz 
# cd memcached-1.2.0 
# ./configure –with-libevent=/usr 
# make 
# make install 
如果中间出现报错，请仔细检查错误信息，按照错误信息来配置或者增加相应的库或者路径。 
安装完成后会把memcached放到 /usr/local/bin/memcached ，

5.测试是否成功安装memcached： 
# ls -al /usr/local/bin/mem* 
-rwxr-xr-x 1 root root 137986 11?? 12 17:39 /usr/local/bin/memcached 
-rwxr-xr-x 1 root root 140179 11?? 12 17:39 /usr/local/bin/memcached-debug

安装Memcache的PHP扩展 
1.在http://pecl.php.net/package/memcache 选择相应想要下载的memcache版本。 
2.安装PHP的memcache扩展

tar vxzf memcache-2.2.1.tgz 
cd memcache-2.2.1 
/usr/local/php/bin/phpize 
./configure –enable-memcache –with-php-config=/usr/local/php/bin/php-config –with-zlib-dir 
make 
make install

3.上述安装完后会有类似这样的提示：

Installing shared extensions: /usr/local/php/lib/php/extensions/no-debug-non-zts-2007xxxx/

4.把php.ini中的extension_dir = “./”修改为

extension_dir = “/usr/local/php/lib/php/extensions/no-debug-non-zts-2007xxxx/”

5.添加一行来载入memcache扩展：extension=memcache.so

memcached的基本设置： 
1.启动Memcache的服务器端： 
# /usr/local/bin/memcached -d -m 10 -u root -l 192.168.0.200 -p 12000 -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，

2.如果要结束Memcache进程，执行：

# kill `cat /tmp/memcached.pid`

也可以启动多个守护进程，不过端口不能重复。

3.重启apache，service httpd restart

4 如果遇到运行memcached时遇到问题，错误提示如下：

/Data/memcached/bin/memcached: error while loading shared libraries: libevent-1.3b.so.1: cannot open shared object file: No such file or directory
则运行 LD_DUBUG=libs 就可以知道memcached启动时库的加载路径。具体如下：
LD_DEBUG=libs /Data/memcached/bin/memcached -v
21404: find library=libpthread.so.0 [0]; searching
21404: search cache=/etc/ld.so.cache
21404: trying file=/lib/tls/libpthread.so.0
21404:
21404: find library=libevent-1.3b.so.1 [0]; searching
21404: search cache=/etc/ld.so.cache
21404: search path=/lib/tls/i686/sse2:/lib/tls/i686:/lib/tls/sse2:/lib/tls:/lib/i686/sse2:/lib/i686:/lib/sse2:/lib:/usr/lib/tls/i686/sse2:/usr/lib/tls/i686:/usr/lib/tls/sse2:/usr/lib/tls:/usr/lib/i686/sse2:/usr/lib/i686:/usr/lib/sse2:/usr/lib (system search path)
21404: trying file=/lib/tls/i686/sse2/libevent-1.3b.so.1
21404: trying file=/lib/tls/i686/libevent-1.3b.so.1
21404: trying file=/lib/tls/sse2/libevent-1.3b.so.1
21404: trying file=/lib/tls/libevent-1.3b.so.1
21404: trying file=/lib/i686/sse2/libevent-1.3b.so.1
21404: trying file=/lib/i686/libevent-1.3b.so.1
21404: trying file=/lib/sse2/libevent-1.3b.so.1
21404: trying file=/lib/libevent-1.3b.so.1
21404: trying file=/usr/lib/tls/i686/sse2/libevent-1.3b.so.1
21404: trying file=/usr/lib/tls/i686/libevent-1.3b.so.1
21404: trying file=/usr/lib/tls/sse2/libevent-1.3b.so.1
21404: trying file=/usr/lib/tls/libevent-1.3b.so.1
21404: trying file=/usr/lib/i686/sse2/libevent-1.3b.so.1
21404: trying file=/usr/lib/i686/libevent-1.3b.so.1
21404: trying file=/usr/lib/sse2/libevent-1.3b.so.1
21404: trying file=/usr/lib/libevent-1.3b.so.1
21404:

然后给libevent-1.3b.so.1建立一个链接：

LD_DEBUG=libs /usr/local/bin/memcached -v
ln -s /usr/local/libevent-1.3b/.libs/libevent-1.3b.so.1 libevent-1.3b.so.1

 

启动memcache

/usr/local/bin/memcached -d -m 10 -u root -l 192.168.0.200 -p 12000 -c 256 -P /tmp/memcached.pid

Memcache环境测试： 
运行下面的php文件，如果有输出This is a test!，就表示环境搭建成功。开始领略Memcache的魅力把！ 
< ?php 
$mem = new Memcache; 
$mem->connect(“127.0.0.1″, 11211); 
$mem->set(‘key’, ‘This is a test!’, 0, 60); 
$val = $mem->get(‘key’); 
echo $val; 
?>