Intel's Vulkan Driver Squeezes Another Optimization Into Mesa 20.0

Patches written two months ago for Intel's ANV open-source Vulkan driver have now been merged ahead of the imminent Mesa 20.0 feature freeze and branching.

The work worth mentioning is allowing HiZ in read-only depth layouts. "These layouts don't mean "sampled" they mean the same thing as DEPTH_STENCIL_OPTIMAL only the client promises to not write the depth or stencil buffer as indicated. Since HiZ depth testing is much faster than non-HiZ depth testing, we really don't want to disable HiZ for these."

The noteworthy aspect of this for end-users is that in one of their common Vulkan benchmarks (Aztec Ruins) the performance on Intel Ice Lake graphics improved by about 5%.

Mesa 20.0 is rounding out to be a great update for Intel Linux graphics users with having various performance optimizations like this, the Intel ANV driver exposes Vulkan 1.2 support, and the default change-over happened to their new Gallium3D driver. Mesa 20.0 should debut as stable around late February and should hopefully make it in time for Ubuntu 20.04 LTS.