Memory requirements and configuration for simultaneous users

Hello,

I am trying to size a server and correctly configure memory. I expect 100 simultaneous users in production with my ScriptCase Project. The Project consists of ScriptCase menu and a number of grids tied to MySQL tables. On the production server, if I configue php.ini memory limit to 64mb, would that typically be sufficient? With 100 simultaneous users does that mean I would need at least 6.4GB memory? What if they have multiple applications open such as with tab or container applications?

Thank you for your thoughts/recommendations.

How many apache threads are running? You can find various tweaks to speed up apache (e.g. by not scanning for .htaccess) maybe you can get a lot of speed from that too. And opcache also can make things a lot faster.