[simon1ltd]

Only if your code is poorly written.

Even on basic hardware, hundreds of requests per second are trivial -- assuming you aren't loading a bunch of files ("require") or making 800 trips to the database to load the site.

I've never found PHPs performance to be a limiting factor, even when I was dealing with dynamic page loads coming in at sustained rates between 50 and 100 per second, and this was on PHP4/5, slow (400MHZ), single core, low ram system. FAMP stack.

I assume Java apps are the same way -- I've never encountered (to my knowledge) a java-based website that wasn't slow. I assume anything that relies on a huge framework probably also had that framework to blame for most performance problems.