1、因为php_memcached是依赖libmemcached库，所以首先安装libmemcached库，需要安装libmemcached-1.x以上版本
wget https://launchpad.net/libmemcached/1.0/1.0.16/+download/libmemcached-1.0.16.tar.gz
tar -zxvf libmemcached-1.0.16.tar.gz
cd libmemcached-1.0.16
./configure -prefix=/usr/local/libmemcached
make && make install
2.安装扩展，这里我们使用php自带的pecl命令来安装php扩展。
/usr/local/webserver/php/bin/pecl install memcached
WARNING: channel "pecl.php.net" has updated its protocols, use "pecl channel-update pecl.php.net" to update
downloading memcached-2.2.0.tgz ...
Starting to download memcached-2.2.0.tgz (70,449 bytes)
.................done: 70,449 bytes
15 source files, building
running: phpize
Configuring for:
PHP Api Version: 20121113
Zend Module Api No: 20121212
Zend Extension Api No: 220121212
libmemcached directory [no] : /usr/local/libmemcached
building in /tmp/pear/temp/pear-build-rootjTskoD/memcached-2.2.0
running: /tmp/pear/temp/memcached/configure --with-libmemcached-dir=/usr/local/libmemcached
...............................
...............................
3、安装完成后在配置文件添加
vim /usr/local/webserver/php/etc/php.ini
extension=memcached.so
4.重启web服务器
service nginx restart
5.重启php
service php-fpm restart
6.验证
php -m|grep memcache
memcache
memcached
另外有需要云服务器可以了解下创新互联cdcxhl.cn，海内外云服务器15元起步，三天无理由+7*72小时售后在线，公司持有idc许可证，提供“云服务器、裸金属服务器、高防服务器、香港服务器、美国服务器、虚拟主机、免备案服务器”等云主机租用服务以及企业上云的综合解决方案，具有“安全稳定、简单易用、服务可用性高、性价比高”等特点与优势，专为企业上云打造定制，能够满足用户丰富、多元化的应用场景需求。