Zink OpenGL-On-Vulkan Sees More Performance Tuning, Regression Fixing

Following my recent RADV+Zink vs. RadeonSI OpenGL benchmarking for various games and workloads, Valve's Zink lead developer Mike Blumenkrantz was hopping on some of the benchmarks where this generic OpenGL-on-Vulkan implementation lagged behind the RadeonSI Gallium3D driver.

In particular, Blumenkrantz has spent time looking at differences in the performance results for the ET: Legacy and BioShock Infinite games where the RadeonSI driver was the clear favorite over Zink.

The BioShock Infinite performance was found to be regressed since last month due to a merge request trying to fix uncached memory readbacks. He's since fixed that last week in Mesa 23.2-devel to check for the cached memory correctly when mapping a buffer.

The ET: Legacy performance was a bit trickier but with profiling he discovered some Zink bottlenecks. With a few tweaks he's managed around a 10% improvement for ET: Legacy though RadeonSI is still leading on his system by about 14%.

More details on this latest round of optimizing for the Zink OpenGL-on-Vulkan Mesa driver via Mike's blog.