安装环境
RHEL 4
Php 5.2.6

所需软件
libevent-1.4.6-stable.tar.gz (http://monkey.org/~provos/libevent/)
memcache-2.2.3.tgz (http://pecl.php.net/package/memcache)
memcached-1.2.6.tar.gz (http://www.danga.com/memcached/)

安装配置

1. 安装libevent
# tar zxf libevent-1.4.6-stable.tar.gz
# cd libevent-1.4.6-stable
# ./configure --prefix=/usr/local/servers/libevent
# make && make install

2. 安装memcached
# tar zxvf memcached-1.2.6.tar.gz
# cd memcached-1.2.6
# ./configure --prefix=/usr/local/servers/memcached --with-libevent=/usr/local/servers/libevent
# make && make install

3. 运行memcached
# /usr/local/servers/memcached -d -m 128 -l localhost -p 11211 -u root

-d 以守护程序（daemon）方式运行 memcached；
-m 设置 memcached 可以使用的内存大小，单位为 M；
-l 设置监听的 IP 地址，如果是本机的话，通常可以不设置此参数；
-p 设置监听的端口，默认为 11211，所以也可以不设置此参数；
-u 指定用户;

如果遇到运行memcached时遇到问题，错误提示如下：

/usr/local/servers/memcached/bin/memcached: error while loading shared libraries: libevent-1.4.so.2: 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 /usr/local/servers/memcached/bin/memcached -v
     10929:     find library=libevent-1.4.so.2 [0]; searching
     10929:      search cache=/etc/ld.so.cache
     10929:      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)
     10929:       trying file=/lib/tls/i686/sse2/libevent-1.4.so.2
     10929:       trying file=/lib/tls/i686/libevent-1.4.so.2
     10929:       trying file=/lib/tls/sse2/libevent-1.4.so.2
     10929:       trying file=/lib/tls/libevent-1.4.so.2
     10929:       trying file=/lib/i686/sse2/libevent-1.4.so.2
     10929:       trying file=/lib/i686/libevent-1.4.so.2
     10929:       trying file=/lib/sse2/libevent-1.4.so.2
     10929:       trying file=/lib/libevent-1.4.so.2
     10929:       trying file=/usr/lib/tls/i686/sse2/libevent-1.4.so.2
     10929:       trying file=/usr/lib/tls/i686/libevent-1.4.so.2
     10929:       trying file=/usr/lib/tls/sse2/libevent-1.4.so.2
     10929:       trying file=/usr/lib/tls/libevent-1.4.so.2
     10929:       trying file=/usr/lib/i686/sse2/libevent-1.4.so.2
     10929:       trying file=/usr/lib/i686/libevent-1.4.so.2
     10929:       trying file=/usr/lib/sse2/libevent-1.4.so.2
     10929:       trying file=/usr/lib/libevent-1.4.so.2
     10929:

然后给libevent-1.4.so.2建立一个链接后再运行memcached：
# ln -s /usr/local/servers/libevent/lib/libevent-1.4.so.2 /lib/libevent-1.4.so.2

4. 安装php的memcache扩展

可以使用php自带的pecl安装程序
# /usr/local/servers/php5/bin/pecl install memcache

也可以从源码安装
# tar zxf memcache-2.2.3.tgz 
# cd memcache-2.2.3
# /usr/local/servers/php5/bin/phpize
# ./configure --enable-memcache=/usr/local/servers/memcached --with-php-config=/usr/local/servers/php5/bin/php-config --with-apxs2=/usr/sbin/apxs
# make && make inst

安装完后会有类似这样的提示：
Installing shared extensions: /usr/local/servers/php5/lib/php/extensions/no-debug-non-zts-20060922/

把这个记住，然后修改php.ini，把

extension_dir = "./"
修改为
extension_dir = "/usr/local/servers/php5/lib/php/extensions/"

并添加一行
extension="no-debug-non-zts-20060922/memcache.so"

5. 用phpinfo查看

测试模块

<?php

$memcache = new Memcache;
$memcache->connect('localhost', 12000) or die ("Could not connect");

$version = $memcache->getVersion();
echo "Server's version: ".$version."<br/>\n";

$tmp_object = new stdClass;
$tmp_object->str_attr = 'test';
$tmp_object->int_attr = 123;

$memcache->set('key', $tmp_object, false, 10) or die ("Failed to save data at the server");
echo "Store data in the cache (data will expire in 10 seconds)<br/>\n";

$get_result = $memcache->get('key');
echo "Data from the cache:<br/>\n";

var_dump($get_result);

?>

显示结果:

Server's version: 1.2.6
Store data in the cache (data will expire in 10 seconds)
Data from the cache:

object(stdClass)[3]  public 'str_attr' => string 'test' (length=4)  public 'int_attr' => int 123