Here’s a few tips and suggestions to lower the ave. memory usage and increase the efficiency of heavy PHP sites delivered via Apache on Linux VPS platforms.
The aim here is to “appropriately scale” both the size of the Apache web server and the way that it responds to connections, so as to provide good performance in smaller RAM VPS environments.
So in CentOS, edit /etc/httpd/conf/httpd.conf and set or change the following settings:
StartServers 3
MinSpareServers 2
MaxSpareServers 3
MaxClients 15
MaxRequestsPerChild 5000
and
KeepAlive On
MaxKeepAliveRequests 100
KeepAliveTimeout 2
The same settings can be applied to the relevant config files for other Linux distributions and there’s some mySQL tuning that I’ll suggest shortly too.
Regards,
Richard.