扩展官网：http://pecl.php.net/package/memcache
扩展下载：http://pecl.php.net/get/memcache-2.2.4.tgz
Memcache扩展安装：
# tar zxvf memcache-2.2.4.tgz
# cd memcache-2.2.4
# /usr/local/php/bin/phpize
# ./configure --with-php-config=/usr/local/php/bin/php-config
# make
# make install
配置
# ls -l /usr/local/php/lib/php/extensions/no-debug-non-zts-20060613/memcache.so
# vim /usr/local/php/lib/php.ini
新增配置内容：
extension_dir = "/usr/local/php/lib/php/extensions/no-debug-non-zts-20060613/"
extension = memcache.so
检查安装结果
# /usr/local/php/bin/php -m
# /usr/local/apache2/bin/apachectl restart