如何在 Linux 下安装 Memcached
源码包准备：
1，http://memcached.googlecode.com/files/memcached-1.4.5.tar.gz
这是最新版的 memcached ，直接下载即可；
Memcached 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-2.0.4；
其实还有一个需要安装的是 PHP 的 PECL 扩展（php_memcache.so），在下面会看到我们使用 apt-get 来得到。
-->先来安装libevent：
# tar zxvf libevent-1.2.tar.gz
# cd libevent-1.2
# ./configure –prefix=/usr
# make
# make install
-->使用下列命令来测试 libevent 是否安装成功：
# cd /usr/lib/
# ls -al libevent*
看看有没有显示：
lrwxrwxrwx 1 root root 21 2010-01-13 08:15 libevent-1.4.so.2 -> libevent-1.4.so.2.1.3
-rw-r--r-- 1 root root 99940 2009-05-18 17:30 libevent-1.4.so.2.1.3
-rw-r--r-- 1 root root 915142 2010-04-25 14:29 libevent.a
-rw-r--r-- 1 root root 574012 2010-04-25 14:29 libevent_core.a
-rwxr-xr-x 1 root root 961 2010-04-25 14:29 libevent_core.la
lrwxrwxrwx 1 root root 22 2010-04-25 14:29 libevent_core.so -> libevent_core.so.3.0.0
lrwxrwxrwx 1 root root 22 2010-04-25 14:29 libevent_core.so.3 -> libevent_core.so.3.0.0
-rwxr-xr-x 1 root root 426876 2010-04-25 14:29 libevent_core.so.3.0.0
-rw-r--r-- 1 root root 341202 2010-04-25 14:29 libevent_extra.a
-rwxr-xr-x 1 root root 968 2010-04-25 14:29 libevent_extra.la
lrwxrwxrwx 1 root root 23 2010-04-25 14:29 libevent_extra.so -> libevent_extra.so.3.0.0
lrwxrwxrwx 1 root root 23 2010-04-25 14:29 libevent_extra.so.3 -> libevent_extra.so.3.0.0
-rwxr-xr-x 1 root root 289438 2010-04-25 14:29 libevent_extra.so.3.0.0
-rwxr-xr-x 1 root root 926 2010-04-25 14:29 libevent.la
-rw-r--r-- 1 root root 7030 2010-04-25 14:29 libevent_pthreads.a
-rwxr-xr-x 1 root root 989 2010-04-25 14:29 libevent_pthreads.la
lrwxrwxrwx 1 root root 26 2010-04-25 14:29 libevent_pthreads.so -> libevent_pthreads.so.0.0.0
lrwxrwxrwx 1 root root 26 2010-04-25 14:29 libevent_pthreads.so.0 -> libevent_pthreads.so.0.0.0
-rwxr-xr-x 1 root root 11186 2010-04-25 14:29 libevent_pthreads.so.0.0.0
lrwxrwxrwx 1 root root 17 2010-04-25 14:29 libevent.so -> libevent.so.3.0.0
lrwxrwxrwx 1 root root 17 2010-04-25 14:29 libevent.so.3 -> libevent.so.3.0.0
-rwxr-xr-x 1 root root 698792 2010-04-25 14:29 libevent.so.3.0.0
-->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
安装完成后会把 memcached 放到 /usr/local/bin/memcached
-->测试是否成功安装 memcached：
# ls -al /usr/local/bin/mem*
看看有没有显示：
-rwxr-xr-x 1 root root 222103 2010-04-25 14:32 /usr/local/bin/memcached
如果一切顺利的话，我们继续往下走：
-->安装 PHP 的 PECL 扩展（php_memcache.so）一句命令：
apt-get install libcache-memcached-perl
跟着命令走吧～～呵呵～
一切就绪以后重启阿帕奇（Apache）或者（Nginx）服务器
使用 phpinfo(); 命令查看 php 配置信息
会有一项：
memcache
memcache support enabled
Version 3.0.1
Revision $Revision: 1.83.2.24 $
Directive Local Value Master Value
memcache.allow_failover 1 1
memcache.chunk_size 32768 32768
memcache.default_port 11211 11211
memcache.hash_function crc32 crc32
memcache.hash_strategy consistent consistent
memcache.max_failover_attempts 20 20
memcache.protocol ascii ascii
memcache.redundancy 1 1
memcache.session_redundancy 2 2
新建 example.php 文件：
1
2 <?php
3
4 $memcache = new Memcache;
5 $memcache->connect('localhost', 11211) or die ("Could not connect");
6
7 $version = $memcache->getVersion();
8 echo "Server's version: ".$version."<br/>\n";
9
10 $tmp_object = new stdClass;
11 $tmp_object->str_attr = 'test';
12 $tmp_object->int_attr = 123;
13
14 $memcache->set('key', $tmp_object, false, 10) or die ("Failed to save data at the server");
15 echo "Store data in the cache (data will expire in 10 seconds)<br/>\n";
16
17 $get_result = $memcache->get('key');
18 echo "Data from the cache:<br/>\n";
19
20 var_dump($get_result);
21
22 ?>
Server's version: 1.4.5
Store data in the cache (data will expire in 10 seconds)
Data from the cache:
object(stdClass)#3 (2) { ["str_attr"]=> string(4) "test" ["int_attr"]=> int(123) }
关于 Memcache 的配置及其使用说明，请参考 PHP 手册的 Memcache Functions 这一章，介绍的很详细！
