When Apache/PHP is running they need to use system resources such as hardware based CPU, RAM, DISK, because of those availability they run and process the inputs.
What gives Apache/PHP very special room of space/comfort/flexibility in terms of hardware tuning? (16core CPU? 32GB RAM? Highest spin disks?)
Example: Industry has 500 PLC (machines/robots/motors etc) simultaneously will be using this server, real time media data and reporting, writing docs, printing, automatically packaging etc etc etc