Memcached is a memory caching system. This will help to increase speed of your vbulletin or wordpress wesites. You can install it easily as follows,
Download the memcached server from http://memcached.org/
wget -c http://memcached.googlecode.com/files/memcached-1.4.15.tar.gz tar -xzf memcached-1.4.15.tar.gz cd memcached-1.4.15/ yum -y install libevent libevent-devel ./configure --prefix=/opt/memcached make make install
Now install init script . I wrote an init script for redhat and centos servers , you can use it to start/stop memcached.
wget -c http://files.syslint.com/conf/memcached.redhar.rc.txt mv -f memcached.redhar.rc.txt /etc/init.d/memcached chmod 750 /etc/init.d/memcached mkdir /var/run/memcached /etc/init.d/memcached start chkconfig --add memcached chkconfig memcached on
Install php-pecl memcache
Download the latest stable memcached from http://pecl.php.net/package/memcache
wget -c http://pecl.php.net/get/memcache-2.2.7.tgz tar -xzf memcache-2.2.7.tgz cd memcache-2.2.7/ phpize ./configure make make install
Now restart apache and create a phpinfo page and test whether the memcache options is showing or not. If it is there then you installed php module . If not you need to check your php.ini settings and enable memcache module
Vbulletin Configuration
Edit the Vb configuration file includes/config.php and uncomment the following lines
$config['Datastore']['class'] = 'vB_Datastore_Memcached'; $i = 0; // First Server $i++; $config['Misc']['memcacheserver'][$i] = '127.0.0.1'; $config['Misc']['memcacheport'][$i] = 11211; $config['Misc']['memcachepersistent'][$i] = true; $config['Misc']['memcacheweight'][$i] = 1; $config['Misc']['memcachetimeout'][$i] = 1; $config['Misc']['memcacheretry_interval'][$i] = 15;
Now restart apache server . Your vbulletin now works with memcached. You can see the performance difference within 1 to 2 hours.
WordPress Configuration
You may just install the wordpress memcached plugin and configure it from wordpress admin panel