Site on OpenGL call performance

Question

I'm searching for reliable data on OpenGL's functions performance. A site that could for example:

1. ...answer me how much more efficient is using glInterleavedArrays compared to gl*Pointer based implementation with strides, or without them. If applicable, show the comparisions on nVidia vs. ATI cards vs. embedded systems.
2. ...answer me how much of a boost is gained in using VBO's vs. non-buffered data in the cases of static, dynamic and stream data.

I'd like to find a site that has "no-bullshit" performance data, not just vague statements like "glInterleavedArrays are usually faster than direct gl*Pointer usage".

Is there such a dream-site? Or at least somewhere where I can get answers to the forementioned questions?

(yes, I know that nothing will beat hand-profiling, but the fact that something works faster on my machine, doesn't mean it's faster generally on all cards...)

Answer 1

It's more about application level benchmarking than measuring performance of individual features, but it might be possible to learn something from specviewperf, especially if it's possible to discover more about what OpenGL mode each benchmark uses to perform it's rendering. The benchmark seems to include some options to tweak usage of display lists, vertex arrays etc, but I don't think SPECs published results go into any analysis of the effects of changing these from the defaults. They don't seem to have any VBO coverage yet.