I can’t see any improvements in performance when I enable the GPU with RealFlow | Cinema 4D. Why?
RealFlow’s Dyverso solver is highly optimized for CPU multi-core and many-core processors. Some GPUs, on the other hand, do not have enough computational power to outperform a 8 or 12 core processor - which is common hardware today. For this reason a GPU-based simulation can be slower than a pure CPU-based simulation.
Which GPU do you recommend for improving performance with RealFlow | Cinema 4D?
We have observed that the number of GPU cores makes the difference. As a simple rule we can say: the more GPU cores, the better. A simulation with a Nvidia Quadro K6000 (2880 cores) is about 3x faster than an Intel Core i7-3930K, for example.
Boards from the GeForce GTX 10 series, e.g. 1080 or 1080 Ti perform very good with RealFlow | Cinema 4D and offer the best value for money.
In some simulations I observe an increased simulation speed with the GPU enabled, but others don’t perform better. Why?
Only the fluid solver is GPU-accelerated, but some processes, e.g. fluid-object collision, are entirely calculated by the CPU. In scenes with many collision objects and other, computationally expensive elements, you might not see a boost in performance by enabling the GPU.
My simulation is slower with the GPU enabled. What happens there?
This is a typical effect when GPUs are not supported or when the GPU is slower than the CPU.
Is it possible to use multiple GPUs or SLI-linked boards?
Sorry, currently not.
CUDA or OpenCL?
Both technologies are supported and the choice is made automatically by RealFlow | Cinema 4D.
How many particles can be simulated with my GPU?
- The amount of VRAM determines the size of the simulation and there is currently no fallback on the mainboard's RAM.
- It's difficult to give solid figures, because the final number depends on the entire scene, the used fluid type, and currently opened programs.
- With 8 GB of VRAM, for example, it is possible to simulate 12-15 millions of → Liquid PBD particles (assuming that the only open program is Cinema 4D with a scene containing one emitter, one fluid container, and one daemon).