My first suspicion would be to rule out window system interaction. If you render to your own VkImage instead of to a swapchain, how fast can you go?
- ajax On Tue, Apr 4, 2023 at 12:56 PM George Karpathios <gkar...@gmail.com> wrote: > Hi list, I hope all is well. > > I would like to ask if there are any known issues regarding the > performance of Lavapipe in Windows 10. > > I'm trying to add support for Vulkan software rendering into a relatively > large 3d modeling/rendering application, so I opted to try Mesa and > Lavapipe. I built LLVM 16.0.0 and Mesa 23.0.1 using the documentation > (thanks for that!). My environment is an 8-core Intel i7 (with an > integrated iGPU) with 32GiB RAM, an nVidia RTX 3070 and Visual Studio > 2019/MSVC. > > The build procedure seems to be ok (Release builds, proper linking with > either MT or MD runtime libraries, proper DLL loading via VK_ICD_FILENAMES) > but the performance I'm getting during runtime is very slow. It looks like > it needs 1-1.5 seconds to render a virtually empty scene (think just a > floor grid of lines) and over 15-20 seconds for a frame of a few thousand > vertices. The CPU utilisation also seems to be low, under 20-25%. > > I understand that the information I provide is probably vague, but at this > point I just want to rule some probable causes out, like is there any > version of LLVM or Mesa or combination of them that is known to have such > issues? Maybe some build/installation configuration parameter or > environment variable that is important in Windows specifically and I may > have missed (I tried tweaking LP_NUM_THREADS but didn't change anything) ? > Anything that could point me in the right direction is highly valuable & > appreciated. > > Also probably worth noting is the fact that the vkcube(pp) demo from the > Vulkan SDK seems to run ok with Lavapipe, but in this case I also notice > (in task manager) a ~50% utilization of the integrated iGPU (why?). In the > aforementioned larger application I don't notice any usage of the > integrated iGPU. > > Any advice on what I could check/double check is more than welcome. Thank > you in advance for your time. > > Best regards, > George > > >
