Intel's Vulkan Linux Driver Increases Instruction Heap - Fix For Overwatch

Intel's ANV open-source Vulkan driver has increased its instruction heap size to 2Gb in order to address a hang experienced with the game Overwatch while this is also likely to help other software/games moving forward.

The merge request by Intel Linux graphics driver engineer Lionel Landwerlin explains:

"Overwatch is generating more than 1Gb of shaders and when trying to use them we end up outside the instruction heap. The EU cannot fetch the instruction and probably executes endless noops, leading to hang."

Thus the solution now in Mesa 23.2 is to increase the instruction heap size to 2Gb.

This merge also added a new "heaps" debug option for dumping information about the driver's heaps. The few hundred lines of code made it into Mesa Git this morning.

It's good seeing the Intel Mesa drivers continue to be enhanced for handling modern games on Linux via Valve's Steam Play. Now if there would be the sparse residency support to land, which is needed for getting various newer games with VKD3D-Proton (Direct3D 12 on Vulkan) to work. The latest there is a work-in-progress branch with the necessary kernel bits being implemented just for the Intel Xe DRM experimental driver with DG2/Alchemist hardware and not every DX12 required feature being in place yet.