I have encountered a negative observation regarding bumblebee. Namely, using optirun the performance of the GPU seems to be an order of magnitude lower than it should be. To be more specific:
I have a laptop with GTX660M, I have (or had, up until yesterday) a bumblebee installation with kernel 3.7.16 running (OS: openSUSE 12.3) where bumblebee was working fine. But after comparing the runtime of my code on the laptop (GTX660M) with an older card (GTX 560) in my desktop PC I have determined the runtime difference to be about 10x - very bad!
After reading up, that the linux kernel 3.12+ comes with support for optimus Graphics I thought of changing to it and did just that. That wrecked pretty much everything. Threads like this do not really help. (especially b/c I'm having trouble applying Arch info to opensuse)
So here's the core question: Does GPU switching work with kernel 3.12+ and which packets are required? Furthermore, does GPGPU work then and what is the performance?