<p>Shortboard stalls can happen due to attribute load/store, attribute interpolation, indexed constant loads, transcendental (rcp, rsqrt, etc.), and other instructions.</p>
<p>So try simplifying complex math, replacing it with lookup tables, or reduce attribute loads.</p>
<p>Hope this helps 5 years later :)</p>
<p><em>Source: <a href="https://docs.nvidia.com/nsight-compute/ProfilingGuide/index.html" rel="nofollow noreferrer">https://docs.nvidia.com/nsight-compute/ProfilingGuide/index.html</a></em></p>

CC BY-SA 4.0
2024-04-16T09:07:59.493Z
2024-04-16T09:07:59.493Z
Yonatan Tepperberg
<p>I'm trying to optimize a geometry pass for a game using dx11 and deferred rendering. (All test are performed on Nvidia GTX 1060 at fixed clock rate)</p>

<p>After profiling with NSight it seems to have very bad utilization of GPU.
<strong>With the top SOL% being SM:36%</strong> </p>

<p><a href="https://i.sstatic.net/AHpxo.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/AHpxo.png" alt="NSight Capture with texture sampling"></a></p>

<p>I decided to investigate and tried to remove all texture sampling and have a pass that would only write constants to the GBuffer and obtain a very different profiling in NSight but not much difference in timing.
I would have expected much more throughput for a shader that basically writes constants.</p>

<p><a href="https://i.sstatic.net/tb0N4.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/tb0N4.png" alt="NSight Capture without any texture sampling"></a></p>

<p>I tried to reduce the GBuffer layout which was originally (FP16 + 2x ARGB32, ARGB32) to 3x ARGB32 with absolutely no difference.</p>

<p>So I'd like to know if somebody has an idea what could be done to improve this pass. Especially if I could be missing something that slows down.</p>

<p>More precise question: <strong>WHAT THE HELL IS Stall Short Scoreboard ???</strong> 
The only info I found about this counter was that</p>

<blockquote>
  <p>Warp was stalled waiting for a scoreboard dependency on a
  MIO (memory input/output) operation</p>
</blockquote>

<p>But I don't understand how I could reduce it. 
Thanks in advance for any help. Hit me if you need any info that could be useful.</p>

CC BY-SA 4.0
2020-11-24T06:06:24.150Z
What happens when you reduce the render resolution to something very low, like 32 x 32 pixels? What do your shaders look like? How often do you bind textures?
Atahan Acar
<rendering><directx11><deferred-rendering>
Optimisation of Geometry Pass
trfd
# Optimisation of Geometry Pass

(Asked by: username_0 on 2019-04-30)

I'm trying to optimize a geometry pass for a game using dx11 and deferred rendering. (All test are performed on Nvidia GTX 1060 at fixed clock rate)

After profiling with NSight it seems to have very bad utilization of GPU.
**With the top SOL% being SM:36%**

[![NSight Capture with texture sampling](https://i.sstatic.net/AHpxo.png)](https://i.sstatic.net/AHpxo.png)

I decided to investigate and tried to remove all texture sampling and have a pass that would only write constants to the GBuffer and obtain a very different profiling in NSight but not much difference in timing.
I would have expected much more throughput for a shader that basically writes constants.

[![NSight Capture without any texture sampling](https://i.sstatic.net/tb0N4.png)](https://i.sstatic.net/tb0N4.png)

I tried to reduce the GBuffer layout which was originally (FP16 + 2x ARGB32, ARGB32) to 3x ARGB32 with absolutely no difference.

So I'd like to know if somebody has an idea what could be done to improve this pass. Especially if I could be missing something that slows down.

More precise question: **WHAT THE HELL IS Stall Short Scoreboard ???**
The only info I found about this counter was that

> Warp was stalled waiting for a scoreboard dependency on a
> MIO (memory input/output) operation

But I don't understand how I could reduce it.
Thanks in advance for any help. Hit me if you need any info that could be useful.

**Tags:** rendering, directx11, deferred-rendering

> **Comments:**
> **username_1**: What happens when you reduce the render resolution to something very low, like 32 x 32 pixels? What do your shaders look like? How often do you bind textures?  

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## 1 answers

### Answer by username_2 on 2024-04-16. Score: 0

Shortboard stalls can happen due to attribute load/store, attribute interpolation, indexed constant loads, transcendental (rcp, rsqrt, etc.), and other instructions.

So try simplifying complex math, replacing it with lookup tables, or reduce attribute loads.

Hope this helps 5 years later :)

*Source: <https://docs.nvidia.com/nsight-compute/ProfilingGuide/index.html>*


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