先下载libmemcached：

wget  https://launchpad.net/libmemcached/1.0/1.0.18/+download/libmemcached-1.0.18.tar.gz

解包：tar -zxf libmemcached-1.0.18.tar.gz

进入解压后的包，编译安装：

./configure --prefix=/usr/local/libmemcached --with-memcached        //注意：--with-memcached这个选项一定要加上

make  &&  make install

安装完成后，开始安装memcached模块：

解包：tar zxvf memcached-2.2.0b1.tgz

进入解压后的包：cd memcached-2.2.0b1

phpize (或者/usr/local/php/bin/phpize)

./configure --with-php-config=/usr/local/php/bin/php-config  --with-libmemcached-dir=/usr/local/libmemcached --disable-memcached-sasl

发现报错：

error: no, sasl.h is not available. Run configure with --disable-memcached-sasl to disable this check

解决方法：

当前目录下找到memcached.h

find / -name memcached.h

出现如下信息：

/home/local/libmemcached-1.0.18/libtest/memcached.h
/home/local/libmemcached-1.0.18/libmemcached-1.0/struct/memcached.h
/home/local/libmemcached-1.0.18/libmemcached-1.0/memcached.h
/home/local/libmemcached-1.0.18/libmemcached/memcached.h
/usr/local/libmemcached/include/libmemcached-1.0/memcached.h
/usr/local/libmemcached/include/libmemcached-1.0/struct/memcached.h
/usr/local/libmemcached/include/libmemcached/memcached.h

修改php_libmemcached_compat.h：

vim php_libmemcached_compat.h

找到include

改成

#ifndef PHP_LIBMEMCACHED_COMPAT
#define PHP_LIBMEMCACHED_COMPAT

/* this is the version(s) we support */
#include </usr/local/libmemcached/include/libmemcached/memcached.h>

将<>里面的内容替换成：/usr/local/libmemcached/include/libmemcached/memcached.h

然后

./configure --with-php-config=/usr/local/php/bin/php-config  --with-libmemcached-dir=/usr/local/libmemcached --disable-memcached-sasl

make && make install

cp /usr/local/php/lib/php/extensions/no-debug-zts-20131226/memcached.so /usr/local/php/extension/memcached.so

vim /usr/local/php/etc/php.ini 添加： extension=memcached.so

/usr/local/apache/bin/apachectl restart

php -m

出现了memcached即安装成功