MaxUnderground has a great review of GPU-accelerated Octane Render system, focusing on lots of the gritty details in the system. Many GPU renderers have come under fire for restrictions in textures and scene sizes (due to limitations of GPU memory), and they’ve broken down the hard limits in their review.
There’s also a limit on the number of texures that can be used, imposed by the CUDA API. This is dependent upon the card architecture you’re using. For pre-Kepler cards the limits are 64 RGBA textures, 32 greyscale textures, 4 HDR RGBA textures and 4 HDR greyscale textures. For Kepler architecture the allowances are more generous with 144 RGBA textures, 68 greyscale textures, 10 HDR RGBA textures, and 10 HDR greyscale textures permitted. Kepler GPUs also introduced the concept of bindless textures which theoretically removes these limits, though this has yet to be integrated into Octane because it would remove support for pre-Kepler cards.
