Instruction tracing does not work on RX 480

[mankeli]

I'm trying to do a instruction tracing from D3D12 app. I have RX 480 GPU, 19.50 driver.

I supply the API PSO hash to the Developer Panel, but when looking at the capture in RGP, the "Instruction Timing" is greyed-out, and the context menu for the event shows greyed-out "View in Instruction timing [Detailed data unavailable]".

My theory is that the GPU is a bit too old for this. If this is the case, could you maybe make it more visible which GPUs actually support this feature?

edit: it's actually possible to get timing trace for other all PSOs i've tried. It might also matter that the shader i'm trying to profile is started with ExecuteIndirect and it's a CS.

edi2: changing drawcall to regular dispatch didn't help

[chesik-amd]

Hi,
One possible cause of this could be if the workload has very few wavefronts.

From the RGP documentation:
Hardware Architecture and Draw Scheduling: Instruction Timing information is only sampled from some of the compute units of the GPU. As a result, it is possible for events with very few waves to not have instruction data even if the API PSO hash was selected. This can happen if the GPU schedules the waves on a compute unit that doesn’t have instruction trace enabled.

If you don't think this is applicable for your case, we would need a test case so we can investigate this issue. If you can share the .rgp file, we can take a look to see if that shows any clues.

Thanks,
Chris

[mankeli]

In this case it has 14416 wavefronts, so I'd guess something should be visible? I'll have to ask from my supervisor if I can share the .rgp

[chesik-amd]

Can you try things out with v1.8 that was released yesterday? There were several cases of this issue fixed in the new release.

https://github.com/GPUOpen-Tools/radeon_gpu_profiler/releases/tag/v1.8