UL releases 3DMark Mesh Shaders Feature test, first results of NVIDIA Ampere and AMD RDNA2 GPUs

UL adds Mesh Shaders test

Today UL released a new DX12 benchmark called Mesh Shaders Feature Test. The test is part of the 3DMark benchmarking software stack. It is now available for free through an update.

The DirectX12 Ultimate API brought four technologies: DX Raytracing, Sampler Feedback, Variable Rate Shading, and Mesh Shaders. UL had already released feature tests for ray tracing and variable-rate shading. The developer has now released a third DX12 test for Mesh Shaders. We have already had a glimpse of a new 3DMark test thanks to Raja Koduri. Intel is currently evaluating its unreleased Xe-HPG gaming GPU, which should debut later this year.

The Mesh Shaders test is relatively short. First, it records a baseline without mesh shading and then compares how much faster is the same scene with the technology enabled.

We have gathered some data from 3DMark featuring the latest graphics cards. Interestingly, NVIDIA Turing GPUs are actually faster in baseline test than NVIDIA Ampere, but the latter see a higher performance increase when mesh shaders are enabled. Overall we are looking at the following average performance increase:

• NVIDIA Ampere: 702%
• AMD RDNA2: 547%
• NVIDIA Turing (RTX): 409%
• NVIDIA Turing: 244%

Do note that we chose the best or close to best scores that were available at the time of writing. It is by no means an accurate representation of each architecture performance. It is only meant to provide a basic understanding of how fast each DirectX12 architecture might be.

Update: AMD has released a new 21.2.2 driver that significantly improves performance in this Feature Test:

DirectX 12 Ultimate adds powerful new features and capabilities to DirectX 12 including DirectX Raytracing Tier 1.1, Mesh Shaders, Sampler Feedback, and Variable Rate Shading (VRS).

3DMark already includes dedicated tests for DirectX Raytracing and Variable Rate Shading.

Today, we’re releasing the 3DMark Mesh Shader feature test, a new test that shows how game engines can improve performance by using mesh shaders in the graphics pipeline.

What is a mesh shader?
In 3D graphics, a mesh is the set of vertices, edges and faces that define the shape of an object. In current graphics pipelines, all the geometry data in a mesh must be processed sequentially before any further steps can be taken. This can be a significant performance bottleneck.

Mesh shaders replace the old model with a new approach to geometry processing that simplifies the graphics pipeline while also giving developers more flexibility and control. Mesh shaders can process small sections of a mesh, called meshlets, in parallel with a much greater degree of flexibility and control.

Test mesh shader performance with 3DMark
The 3DMark Mesh Shader feature test shows how game engines can improve performance by using the mesh shader pipeline to efficiently cull geometry that is not visible to the camera.

The test scene is a hall containing many rows of highly detailed, carved pillars. As the camera moves through the scene, the pillars in the foreground block the view of those further back.

The test runs in two passes. The first pass uses a traditional approach to geometry culling to provide a performance baseline. The second pass uses mesh shaders to efficiently cull hidden meshlets. The result of the test is the average frame rate for each pass and the difference between the two expressed as a percentage.

Interactive mode
The 3DMark Mesh Shader feature test includes an interactive mode that helps you visualize the benefits of using mesh shaders. You can pause and jump to different parts of the timeline and change settings in real-time. Use visualizer options to highlight meshlets or see the level of detail (LOD) used for each meshlet.

Source: Steam