Phoronix published a review on the Radeon RX 560 Linux OpenGL/Vulkan Benchmarks
A quote from the article:
Last week the "Polaris Evolved" Radeon RX 560 graphics card launched. I picked up a Sapphire Radeon RX 560 for Linux testing and have those results to share today for OpenGL and Vulkan workloads under Linux using the 4.12 development kernel and Mesa 17.2-dev compared to a range of Radeon and GeForce graphics cards.Radeon RX 560 Linux OpenGL/Vulkan Benchmarks @ Phoronix