research-article

Megakernels considered harmful: wavefront path tracing on GPUs

Authors:

Timo AilaAuthors Info & Claims

HPG '13: Proceedings of the 5th High-Performance Graphics Conference

Pages 137 - 143

https://doi.org/10.1145/2492045.2492060

Published: 19 July 2013 Publication History

Abstract

When programming for GPUs, simply porting a large CPU program into an equally large GPU kernel is generally not a good approach. Due to SIMT execution model on GPUs, divergence in control flow carries substantial performance penalties, as does high register us-age that lessens the latency-hiding capability that is essential for the high-latency, high-bandwidth memory system of a GPU. In this paper, we implement a path tracer on a GPU using a wavefront formulation, avoiding these pitfalls that can be especially prominent when using materials that are expensive to evaluate. We compare our performance against the traditional megakernel approach, and demonstrate that the wavefront formulation is much better suited for real-world use cases where multiple complex materials are present in the scene.

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Cited By

Duan XLiu JWang X(2024)Real-Time Wave Simulation of Large-Scale Open Sea Based on Self-Adaptive Filtering and Screen Space Level of DetailJournal of Marine Science and Engineering10.3390/jmse1204057212:4(572)Online publication date: 28-Mar-2024
https://doi.org/10.3390/jmse12040572
Stein CHellmuth CConty Estevez ALecocq PGritz L(2024)Spear: Across the Streaming Multiprocessors: Porting a Production Renderer to the GPUProceedings of the 2024 Digital Production Symposium10.1145/3665320.3670988(1-9)Online publication date: 24-Jul-2024
https://dl.acm.org/doi/10.1145/3665320.3670988
Zeltner TRousselle FWeidlich AClarberg PNovák JBitterli BEvans ADavidovič TKallweit SLefohn A(2024)Real-time Neural Appearance ModelsACM Transactions on Graphics10.1145/365957743:3(1-17)Online publication date: 20-Apr-2024
https://dl.acm.org/doi/10.1145/3659577
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Index Terms

Megakernels considered harmful: wavefront path tracing on GPUs
1. Computing methodologies
  1. Computer graphics
    1. Graphics systems and interfaces
    2. Rendering
      1. Ray tracing
  2. Parallel computing methodologies
    1. Parallel programming languages
2. Software and its engineering
  1. Software notations and tools
    1. General programming languages
      1. Language types
        Parallel programming languages

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Published In

cover image ACM Conferences

HPG '13: Proceedings of the 5th High-Performance Graphics Conference

July 2013

149 pages

ISBN:9781450321358

DOI:10.1145/2492045

General Chairs:
Steve Molnar
NVIDIA
,
Jens Krüger
IVDA Saarland University, Germany
,
Program Chairs:
Tim Purcell
NVIDIA
,
Warren Hunt
Google

Copyright © 2013 ACM.

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SIGGRAPH: ACM Special Interest Group on Computer Graphics and Interactive Techniques
EUROGRAPHICS: The European Association for Computer Graphics

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Published: 19 July 2013

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HPG '13

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EUROGRAPHICS

HPG '13: High Performance Graphics

July 19 - 21, 2013

California, Anaheim

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HPG '13 Paper Acceptance Rate 15 of 44 submissions, 34%;

Overall Acceptance Rate 15 of 44 submissions, 34%

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Cited By

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https://doi.org/10.3390/jmse12040572
Stein CHellmuth CConty Estevez ALecocq PGritz L(2024)Spear: Across the Streaming Multiprocessors: Porting a Production Renderer to the GPUProceedings of the 2024 Digital Production Symposium10.1145/3665320.3670988(1-9)Online publication date: 24-Jul-2024
https://dl.acm.org/doi/10.1145/3665320.3670988
Zeltner TRousselle FWeidlich AClarberg PNovák JBitterli BEvans ADavidovič TKallweit SLefohn A(2024)Real-time Neural Appearance ModelsACM Transactions on Graphics10.1145/365957743:3(1-17)Online publication date: 20-Apr-2024
https://dl.acm.org/doi/10.1145/3659577
Miller BSawhney RCrane KGkioulekas I(2024)Walkin’ Robin: Walk on Stars with Robin Boundary ConditionsACM Transactions on Graphics10.1145/365815343:4(1-18)Online publication date: 19-Jul-2024
https://dl.acm.org/doi/10.1145/3658153
Tokuyoshi YEto K(2024)Bounded VNDF Sampling for the Smith-GGX BRDFProceedings of the ACM on Computer Graphics and Interactive Techniques10.1145/36512917:1(1-18)Online publication date: 13-May-2024
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Huang JIizuka ATanaka HKomura TKitamura Y(2024)Online Neural Path Guiding with Normalized Anisotropic Spherical GaussiansACM Transactions on Graphics10.1145/364931043:3(1-18)Online publication date: 9-Apr-2024
https://dl.acm.org/doi/10.1145/3649310
Wu QBauer DDoyle MMa K(2024)Interactive Volume Visualization via Multi-Resolution Hash Encoding Based Neural RepresentationIEEE Transactions on Visualization and Computer Graphics10.1109/TVCG.2023.329312130:8(5404-5418)Online publication date: Aug-2024
https://doi.org/10.1109/TVCG.2023.3293121
Song ZGan LXiang SWang YDuan XYang G(2024)Enabling High-Performance Physical Based Rendering on New Sunway Supercomputer2024 IEEE International Parallel and Distributed Processing Symposium (IPDPS)10.1109/IPDPS57955.2024.00032(277-288)Online publication date: 27-May-2024
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Yalçıner BAkyüz A(2024)Path guiding for wavefront path tracing: A memory efficient approach for GPU path tracersComputers & Graphics10.1016/j.cag.2024.103945121(103945)Online publication date: Jun-2024
https://doi.org/10.1016/j.cag.2024.103945
Zingsheim DKlein R(2024)Learning subsurface scattering solutions of tightly-packed granular media using optimal transportComputers & Graphics10.1016/j.cag.2024.103895119(103895)Online publication date: Apr-2024
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