"""Think about it, in the 'full stack' of browser -> client -> interweb -> web server -> app server -> db server the little bit of code that you wrote is minuscule compared to what you didn't write."""
This. The old saying "don't prematurely optimize" has never been truer. Too bad it's gotten harder to profile. Unless you write a boring CGI, one-load-per-page site, you're never going to be able to get all of that information server-side. The only way is with browser-based testing frameworks... Sigh.
I've used Dummynet extensively (with great satisfaction!), but I've been looking for a more recently updated alternative (preferably with good Linux support). Is anyone aware of any such thing?
"netem provides Network Emulation functionality for testing protocols by emulating the properties of wide area networks. The current version emulates variable delay, loss, duplication and re-ordering."