Intel Adds New Option To Help In Profiling Their Open-Source Vulkan Driver

A two year old merge request finally made it to mainline today for Mesa 23.1 to enhance in profiling the open-source Mesa Vulkan drivers.

The new option added to Mesa's Vulkan windowing system integration (WSI) is a headless swapchain. This is for turning every swapchain creation into a null swapchain and in turn not presenting anything, which in turn allows the application to churn out as many frames as possible.

The intent when this mode is activated via the "MESA_VK_WSI_NULL_SWAPCHAIN" variable is to help identify slow spots within the Vulkan driver's command buffer building code path.

This Mesa Vulkan headless swapchain option was started by Intel's Lionel Landwerlin two years ago but took until today to be mainlined.

This isn't directly useful to Linux gamers/enthusiasts but can indirectly benefit them with Vulkan driver developers being able to leverage the headless swapchain for helping to uncover slow code paths. As this is just touching the common Mesa Vulkan WSI code and not ANV-specific, this can help out other Mesa Vulkan drivers too beyond Intel. See this MR for more details if interested.