EUs Stalled in VS
The metric EUs Stalled in VS represents the percentage of overall GPU time that the EUs were stalled in Vertex Shader instructions.
This metric does not include the total amount of time stalled in the vertex shader, but only the fraction of the time when vertex shader stalls were causing the entire EU to stall. The entire EU stalls when all of its threads are stalled.
- If EUs Stalled in VS is 50% it means that half of the overall GPU time was spent stalled on Vertex Shader instructions.
If EUs Stalled in VS is 0% it means that no Vertex Shader was associated with selected rendering calls or Vertex Shader threads were not causing EUs stalls.
- This metric is important if vertex processing seems to be the bottleneck for selected rendering calls. If EUs Active in VS accounts for most of the EU active time, then to improve performance you may need to simplify the vertex shader or simplify and optimize geometry.
- If EUs Stalled in VS is significant you need to concentrate on vertex shader code to find reasons causing stalls.
Look into the Shaders Tab in the Intel® GPA Frame Analyzer to inspect the shader code.