239c88e8
by Giovanni Mascellani at 2024-12-05T21:00:03+01:00
vkd3d: Do not use more than a few million descriptors in Vulkan heap set layouts.
Currently, when using Vulkan heaps, we create descriptor set
layouts with as many descriptors as allowed by the Vulkan
implementation limits. For some implementations this can mean
hundreds of millions of descriptors or more, which is wasteful,
given that even on the best resource binding tier Direct3D 12
applications should not expect to have more than a million usable
descriptors.
Recently this began being a problem, because since Mesa 24.2.7
the Intel driver advertises more than 200 million descriptors,
but pipeline compilation takes linear RAM in the number of
descriptors declared in the pipeline layout. This means that
compiling even a simple shader requires 10-20 GB of RAM.
In order to avoid using too much memory, with this commit we clamp
the number of descriptors declared in the set layouts to how many
we actually need to guarantee tier 3 resource binding support.