Seamless Compute and OpenGL Graphics Development in

NVIDIA® Nsight 3.0™ Visual Studio Edition …and Beyond

3/20/2013

NVIDIA Confidential

Agenda

Computational Graphics and Visual Computing

Developer Challenges

Maximus™

Getting help from Nsight

…and Beyond

Conclusion and Q&A

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Computational Graphics – Visual Computing

Deferred Shading

Ambient Occlusion

Simulation & Visualization

Medical imaging

Manufacturing

…

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Compute Shader Based Deferred Shading

Graphics pipeline rasterizes gbuffers for opaque surfaces

Compute pipeline uses gbuffers

— culls light sources

— computes lighting

— combines with shading

Johann Anderson - Compute Shader Based Deferred Shading

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Multi-GPU Platform Overview

OS

WDDM

GPU Driver

APP

I/O H

UB

MEM

MEM

CE1

CE2

<<<.>>>

GPU

MEM

CE1

CE2

<<<.>>>

GPU CPU

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Single-GPU Simulation and Visualization

Fn-1

<<<…>>>

Fn

<<<…>>>

<<<…>>>

<<<…>>>

Kernels

Mem. xfers

Draw

Mem. xfers

Mem. xfers

1

2

CPU

GPU

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Multi-GPU Simulation and Visualization

Fn-1 Fn+1

<<<…>>>

Fn

<<<…>>>

<<<…>>>

<<<…>>>

<<<…>>> <<<…>>>

<<<…>>>

Kernels

Mem. xfers

<<<…>>>

Draw

Mem. xfers 2

1

?

CPU

GPU

GPU

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Developer Challenges

Debugging GPU Compute and Graphics and interop

Context switching overhead

Multi-Core/Multi-GPU race conditions

Data transfers – host-to-device, device-to-host, P2P

Asynchronous transfers

Multi-core/Multi-threaded

Multi-GPU – Graphics/Graphics, Graphics/Compute

Concurrent kernel execution

Driver models (TCC/WDDM)

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NVIDIA® Maximus™

Compute Companion

Processor

NVIDIA® MAXIMUS

Professional Graphics

Processor

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NVIDIA® Nsight™ Visual Studio Edition Visual Studio integrated development for GPU and CPU

Profile Debug Build

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NVIDIA Nsight for Graphics Developers OpenGL 4.2, Direct3D 9/11

• Frame debugger - OpenGL 4.2, Direct3D 9/11

• HLSL and GLSL Shader debugger

• Frame profiler - OpenGL 4.2, Direct3D 9/11

• Application and system trace

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NVIDIA Nsight for Compute Developers CUDA 4.2 and 5.0 and Maximus™

• CUDA Debugger

• CUDA Memory Checker

• Application and system trace

• CUDA Profiler

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Two Methods for Fast Ray-Cast Ambient

Occlusion Render depth & normal buffers using OpenGL

Calculates AO using CUDA

Deferred shading in OpenGL Fn-1

Fn

<<<…>>> Kernels

Mem. xfers

Draw

Mem. xfers

GPU

GPU

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PhysX Fracture Demo

Fracture computation in CUDA

PhysX GPU Rigid body collision in CUDA

OpenGL for rendering opaque scene and composite final image

Fn-1

Fn

<<<…>>> Kernels

Mem. xfers

Draw

Mem. xfers

GPU

GPU <<<…>>>

<<<…>>> … <<<…>>>

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Macro Analysis Heterogeneous System Utilization

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NVIDIA Tools Extension API

Markers and Ranges

— Colors, string and payload

NVTX

— Host code decoration

— Frame Debugger scrubber

— Frame Profiling

— System Trace

NVTXT

— Custom data provider for System Trace

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High Performance Areas to Watch For

Kernel execution concurrency

Asynchronous memory transfers (Quadro/Tesla)

WDDM kernel fifos

Minimize Compute/Graphics context switches on a single

GPU

Multi-GPU and P2P xfers

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Single-GPU Memory Transfers

OS

WDDM

GPU Driver

APP

I/O H

UB

MEM

MEM

CE1

CE2

<<<.>>>

GPU

MEM

CE1

CE2

<<<.>>>

GPU CPU

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Multi-GPU memory transfers – P2H2P

OS

WDDM

GPU Driver

APP

I/O H

UB

MEM

MEM

CE1

CE2

<<<.>>>

GPU

MEM

CE1

CE2

<<<.>>>

GPU CPU

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Multi-GPU memory transfers – P2P

OS

WDDM

GPU Driver

APP

I/O H

UB

MEM

MEM

CE1

CE2

<<<.>>>

GPU

MEM

CE1

CE2

<<<.>>>

GPU CPU

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Multi-GPU memory transfers

CUDA

Context OpenGL

Context

RAM

Buffer

GPU 1 GPU 2

CUDA memcpy glBufferSubData

CUDA

Context

Aux.

CUDA

Context

Buffer

GPU 1 GPU 2

CUDA memcpy

OpenGL

Context

API Interop

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…Beyond

GLSL Compute shader

Single GPU Graphics and Compute debugging

Full Compute and Graphics capture and replay

Source code generation of Compute and Graphics trace

Intra-frame debugging– snapshots of interop buffers…

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Intra-Frame CUDA/OpenGL interop support

Fn-1

<<<…>>>

Fn

<<<…>>>

<<<…>>>

<<<…>>>

Kernels

Mem. xfers

Draw

Mem. xfers

<<<…>>>

GPU

GPU

CPU

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Conclusion

Multi-GPU developer tools are available

Start GPU Debugging…

Use NVToolsExt

System Trace is your friend

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Q&A

Download

— http://www.nvidia.com/nsight

Nsight Visual Studio Edition Developer Forums

— https://devtalk.nvidia.com/default/board/84/nsight-visual-studio-edition

Nsight documentation — Start All Programs NVIDIA Nsight Visual Studio Edition 3.0 User Guide

— http://http.developer.nvidia.com/NsightVisualStudio/3.0/Documentation/UserGuide/HTML/Nsight

_Visual_Studio_Edition_User_Guide.htm

Nsight instruction videos

— http://www.gputechconf.com/object/gtc-express-webinar.html

Special Thanks – Tero Karas, Shalini Venkataraman, David Luebke for the demo content