Performance help! Waiting on server for ~280ms

[eluser]georgeedwards[/eluser]
Hello everyone.

In the app I'm currently developing, I've been doing a lot of benchmarking and performance tweaking, but I think I've hit a dead end. It seems to be CodeIgniter related.

Using something like FireBug, I can see that my pages are always having to "wait" on the server for circa 280-300ms before they start rendering.

I've tried stripping off all autoloaded libs, helpers, no db access, etc etc, and just had a "naked" skeleton controller and still hit the same problem - shaving maybe 80ms off tops to about 200ms.

Is this delay normal? Maybe it's server related? I don't think it's PHP/Apache per se, as using raw PHP I get much better results around 10-12ms.

Any help would be gratefully received. Thank you.