My dedicated server is getting an huge RAM usage. I'm hosting 15 wordpress based sites and 2 based on Magento. I'm using Memcached on few of them. I need to free caches every day to drop the memory usage. It runs latest version of ISPConfig, Debian Wheezy and it's a SYS-IP-5 dedicated server from Ovh http://www.soyoustart.com/it/offerte/sys-ip-5.xml I attach a screenshot of top command. Any suggestion? What could cause the problem? Thank you.