As shown in recent benchmarks of the RADV Vulkan driver, while the Radeon RX Vega GPU support is now considered conformant and fully-functioning, it’s not yet as well optimized as earlier generations of GPUs with this open-source Radeon Vulkan driver. Fortunately, it looks like Bas Nieuwenhuizen is working on more performance optimizations…

Source: Phoronix – RADV Driver Lands Support For Binning With Vega