Intel Gallium3D Gets Another Performance Optimization Around IO Vectorization

The Intel Gallium3D driver has seen another performance optimization now merged into the Mesa 19.2 development code for its stable release next quarter.

New to the Intel Iris Gallium3D driver is support for vectorizing their IO. In some graphics tests with Skylake GT4e graphics it was able to enhance the performance by about 9% but in other cases less than 1%. The big improvement in performance came when this IO vectorization was able to help in eliminating all spilling in the geometry shaders.

Lead Intel Gallium3D developer Kenneth Graunke added re-vectorize shader IO support to the Mesa NIR state tracker code for drivers wanting to re-vectorize their shader IO after varying optimizations are complete. And then flipping on the support to vectorize the IO for the Intel Gallium3D driver.

The Intel Gallium3D driver has already been performing largely at-par to their classic OpenGL Mesa driver at least so by the time of Mesa 19.2.0 in August it will be interesting to see how performant this open-source GL driver is for current generation Intel graphics hardware. Intel is still aiming for this Gallium3D driver to be their default Linux OpenGL solution by year's end and given their near-daily improvements and optimizations, it's looking good for hitting that milestone on time.